Greater cervical kyphosis during flexion increases the risk of kyphotic deformity after laminoplasty in patients with cervical spondylotic myelopathy

Kyphotic deformity following the loss of cervical lordosis can lead to unfavourable neurological recovery after cervical laminoplasty (CLP); therefore, it is essential to identify its risk factors. Recent studies have demonstrated that the dynamic parameters of the cervical spine, based on baseline flexion/extension radiographs, are highly useful to estimate the loss of cervical lordosis after CLP. However, it remains unclear whether such dynamic parameters can predict kyphotic deformity development after CLP. Hence, the present study aimed to investigate whether the dynamic parameters could predict kyphotic deformity in patients with cervical spondylotic myelopathy (CSM) after CLP. This retrospective study included 165 patients, consisting of 10 and 155 patients with and without cervical kyphosis of C2-C7 angle ≤ -10° at the final follow-up period, respectively. Among the static and dynamic parameters of the cervical spine, greater cervical kyphosis during flexion (fC2-C7 angle) demonstrated the best discrimination between these two cohorts, with an optimal cutoff value of -27.5°. Meanwhile, greater gap range of motion (gROM = flexion ROM - extension ROM ) had the highest ability to predict a loss of ≥ 10° in C2-C7 angle after CLP, with an optimal cutoff value of 28.5°. This study suggests that in patients with CSM, fC2-C7 angle ≤ -25° on baseline radiographs is a potential risk for kyphotic deformity after CLP. In clinical practice, the patients with this criterion (fC2-C7 angle ≤ -25°) along with gROM ≥ 30° are at high risk of developing significant kyphotic deformity after CLP.

Neutron scattering and neural-network quantum molecular dynamics investigation of the vibrations of ammonia along the solid-to-liquid transition

Vibrational spectroscopy allows us to understand complex physical and chemical interactions of molecular crystals and liquids such as ammonia, which has recently emerged as a strong hydrogen fuel candidate to support a sustainable society. We report inelastic neutron scattering measurement of vibrational properties of ammonia along the solid-to-liquid phase transition with high enough resolution for direct comparisons to ab-initio simulations. Theoretical analysis reveals the essential role of nuclear quantum effects (NQEs) for correctly describing the intermolecular spectrum as well as high energy intramolecular N-H stretching modes. This is achieved by training neural network models using ab-initio path-integral molecular dynamics (PIMD) simulations, thereby encompassing large spatiotemporal trajectories required to resolve low energy dynamics while retaining NQEs. Our results not only establish the role of NQEs in ammonia but also provide general computational frameworks to study complex molecular systems with NQEs.

Long-term safety of desmopressin orally disintegrating tablets in men with nocturia due to nocturnal polyuria: Interim results of a specified drug use-results survey in Japan

OBJECTIVES

This interim report presents the 12-week results of a post-marketing surveillance evaluating the safety of desmopressin orally disintegrating tablets 25 and 50 μg in Japanese men with nocturia due to nocturnal polyuria.

METHODS

Of the planned study population of 1000 Japanese men receiving desmopressin for the first time for nocturia due to nocturnal polyuria, 971 cases were enrolled. In this interim analysis, 9 cases, including 6 registry violations and 3 cases of unconfirmed desmopressin dosing, were excluded from the 354 case report forms collected and fixed by the end of December 2021, and data up to 12 weeks after administration in 345 cases were defined as the safety analysis set.

RESULTS

The mean age was 74.5 ± 9.9 years and 88.7% of the survey participants were aged ≥65 years. Desmopressin was started at a dose of 25 μg in 153 cases (44.3%). There were 102 adverse drug reactions (ADRs) reported in 71 cases, including 6 serious ADRs in 3 cases (0.9%). The most common ADR was hyponatremia occurring in 29 cases (8.4%). Eight of the hyponatremic cases were asymptomatic. Symptoms were resolved or slightly improved within 4 weeks of onset in 13 of 29 cases of hyponatremia. In addition, hyponatremia occurred in 11 of 217 cases (5.1%), with a serum sodium level before the administration of desmopressin of ≥140 mmol/L, and in 13 of 87 cases (14.9%), with a level of 135-139 mmol/L, and was not measured in 5 hyponatremia cases. Patient characteristics that showed significant differences in the occurrence of hyponatremia included body weight, body mass index, renal function, and pretreatment serum sodium level. Regular monitoring of serum sodium is necessary for early detection of hyponatremia.

CONCLUSIONS

Hyponatremia was the most common ADR when desmopressin orally disintegrating tablets were used to treat nocturia due to nocturnal polyuria over a 12-week period.

The role of metabolism in cardiac development

Metabolism is the fundamental process that sustains life. The heart, in particular, is an organ of high energy demand, and its energy substrates have been studied for more than a century. In recent years, there has been a growing interest in understanding the role of metabolism in the early differentiation of pluripotent stem cells and in cancer research. Studies have revealed that metabolic intermediates from glycolysis and the tricarboxylic acid cycle act as co-factors for intracellular signal transduction, playing crucial roles in regulating cell behaviors. Mitochondria, as the central hub of metabolism, are also under intensive investigation regarding the regulation of their dynamics. The metabolic environment of the fetus is intricately linked to the maternal metabolic status, and the impact of the mother's nutrition and metabolic health on fetal development is significant. For instance, it is well known that maternal diabetes increases the risk of cardiac and nervous system malformations in the fetus. Another notable example is the decrease in the risk of neural tube defects when pregnant women are supplemented with folic acid. These examples highlight the profound influence of the maternal metabolic environment on the fetal organ development program. Therefore, gaining insights into the metabolic environment within developing fetal organs is critical for deepening our understanding of normal organ development. This review aims to summarize recent findings that build upon the historical recognition of the environmental and metabolic factors involved in the developing embryo.

Atlas of fetal metabolism during mid-to-late gestation and diabetic pregnancy

Mounting evidence suggests metabolism instructs stem cell fate decisions. However, how fetal metabolism changes during development and how altered maternal metabolism shapes fetal metabolism remain unexplored. We present a descriptive atlas of in vivo fetal murine metabolism during mid-to-late gestation in normal and diabetic pregnancy. Using 13C-glucose and liquid chromatography-mass spectrometry (LC-MS), we profiled the metabolism of fetal brains, hearts, livers, and placentas harvested from pregnant dams between embryonic days (E)10.5 and 18.5. Our analysis revealed metabolic features specific to a hyperglycemic environment and signatures that may denote developmental transitions during euglycemic development. We observed sorbitol accumulation in fetal tissues and altered neurotransmitter levels in fetal brains isolated from hyperglycemic dams. Tracing 13C-glucose revealed disparate fetal nutrient sourcing depending on maternal glycemic states. Regardless of glycemic state, histidine-derived metabolites accumulated in late-stage fetal tissues. Our rich dataset presents a comprehensive overview of in vivo fetal tissue metabolism and alterations due to maternal hyperglycemia.

Clinical outcome of surgical management of mild cervical compressive myelopathy based on minimum clinically important difference

BACKGROUND CONTEXT

Cervical compressive myelopathy (CCM), caused by cervical spondylosis (cervical spondylotic myelopathy [CSM]) or ossification of the posterior longitudinal ligament (OPLL), is a common neurological disorder in the elderly. For moderate/severe CCM, surgical management has been the first-line therapeutic option. Recently, surgical management is also recommended for mild CCM, and a few studies have reported the surgical outcome for this clinical population. Nonetheless, the present knowledge is insufficient to determine the specific surgical outcome of mild CCM.

PURPOSE

To examine the surgical outcomes of mild CCM while considering the minimum clinically important difference (MCID).

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

Patients who underwent subaxial cervical surgery for CCM caused by CSM and OPLL between 2013 and 2022 were enrolled.

OUTCOME MEASURES

The Japanese Orthopedic Association score (JOA score) was employed as the clinical outcomes. Based on previous reports, the JOA score threshold to determine mild myelopathic symptoms was set at ≥14.5 points, and the MCID of the JOA score for mild CCM was set at 1 point.

METHODS

The patients with a JOA score of ≥14.5 points at baseline were stratified into the mild CCM and were examined while considering the MCID. The mild CCM cohort was dichotomized into the improvement group, including the patients with an achieved MCID (JOA score ≥1 point) or with a JOA score of 17 points (full mark) at 1 year postoperatively, and the nonimprovement group, including the others. Demographics, symptomatology, radiographic findings, and surgical procedure were compared between the two groups and studied using the receiver operating characteristic (ROC) curve.

RESULTS

Of 335 patients with CCM, 43 were stratified into the mild CCM cohort (mean age, 58.5 years; 62.8% male). Among them, 25 (58.1 %) patients were assigned to the improvement group and 18 (41.9 %) were assigned to the nonimprovement group. The improvement group was significantly younger than the nonimprovement group; however, other variables did not significantly differ. ROC curve analysis showed that the optimal cutoff point of the patient's age to discriminate between the improvement and nonimprovement groups was 58 years with an area under the curve of 0.702 (p=.015).

CONCLUSIONS

In the present study, the majority of patients with mild CCM experienced improvement reaching the MCID of JOA score at 1 year postoperatively. The present study suggests that for younger patients with mild CCM, especially those aged below 58 years, subjective neurological recovery is more likely to be obtained. Meanwhile, the surgery takes on a more prophylactic significance to halt disease progression for older patients. The results of this study can help in the decision-making process for this clinical population.

Ultrasonographic Evaluation of Upper Esophageal Sphincter for Dysphagia During the Acute Postoperative Phase of Anterior Cervical Surgery

STUDY DESIGN

A retrospective study.

OBJECTIVE

To verify the pathophysiology of dysphagia during the acute postoperative phase of anterior cervical surgery and to identify its predictive features, using ultrasonographic (US) examination for upper esophageal sphincter (UES).

SUMMARY OF BACKGROUND DATA

There are no clinical studies investigating dysphagia after anterior cervical surgery, using US examination for UES.

MATERIALS AND METHODS

We enrolled patients who underwent anterior cervical spine surgery between August 2018 and March 2022. Dysphagia was evaluated using the Eating Assessment Tool-10 (EAT-10) questionnaires. The US examination was performed preoperatively and 2 weeks postoperatively. Three US parameters for morphologic measurements (outer diameter, inner diameter, and muscle thickness) and 4 for functional measurements (displacement, time to relax, passing duration, and time to contract) were assessed. To verify the pathophysiology of postoperative dysphagia, we examined the change in the ratios of US parameters (=US parameter2 weeks postoperatively/US parameterat baseline) and the existence of significant correlations with change in the EAT-10 score (=EAT-102 weeks postoperatively-EAT-10at baseline). To identify the predictive features, the baseline US parameters were compared between dysphagia (+) and dysphagia (-) groups.

RESULTS

A total of 46 patients (mean age, 61.3 y; 78.3% male) were included for analysis. A greater increase of the EAT-10 score after surgery was positively correlated with change ratios of the muscle thickness and time to contract and negatively with change ratio of the inner diameter. The dysphagia (+) group exhibited significantly greater inner diameter and smaller muscle thickness at baseline than the dysphagia (-) group.

CONCLUSION

Dysphagia during the acute postoperative phase of anterior cervical surgery is caused by the physical narrowing of the inner lumen due to muscle thickening of the UES and sphincter contractile dysfunction. In addition, a baseline UES morphology characterized by a greater inner diameter and a thinner muscle layer is predictive of postoperative dysphagia.

Rtf1-dependent transcriptional pausing regulates cardiogenesis

During heart development, a well-characterized network of transcription factors initiates cardiac gene expression and defines the precise timing and location of cardiac progenitor specification. However, our understanding of the post-initiation transcriptional events that regulate cardiac gene expression is still incomplete. The PAF1C component Rtf1 is a transcription regulatory protein that modulates pausing and elongation of RNA Pol II, as well as cotranscriptional histone modifications. Here we report that Rtf1 is essential for cardiogenesis in fish and mammals, and that in the absence of Rtf1 activity, cardiac progenitors arrest in an immature state. We found that Rtf1's Plus3 domain, which confers interaction with the transcriptional pausing and elongation regulator Spt5, was necessary for cardiac progenitor formation. ChIP-seq analysis further revealed changes in the occupancy of RNA Pol II around the transcription start site (TSS) of cardiac genes in rtf1 morphants reflecting a reduction in transcriptional pausing. Intriguingly, inhibition of pause release in rtf1 morphants and mutants restored the formation of cardiac cells and improved Pol II occupancy at the TSS of key cardiac genes. Our findings highlight the crucial role that transcriptional pausing plays in promoting normal gene expression levels in a cardiac developmental context.

Notch and retinoic acid signals regulate macrophage formation from endocardium downstream of Nkx2-5

Hematopoietic progenitors are enriched in the endocardial cushion and contribute, in a Nkx2-5-dependent manner, to tissue macrophages required for the remodeling of cardiac valves and septa. However, little is known about the molecular mechanism of endocardial-hematopoietic transition. In the current study, we identified the regulatory network of endocardial hematopoiesis. Signal network analysis from scRNA-seq datasets revealed that genes in Notch and retinoic acid (RA) signaling are significantly downregulated in Nkx2-5-null endocardial cells. In vivo and ex vivo analyses validate that the Nkx2-5-Notch axis is essential for the generation of both hemogenic and cushion endocardial cells, and the suppression of RA signaling via Dhrs3 expression plays important roles in further differentiation into macrophages. Genetic ablation study revealed that these macrophages are essential in cardiac valve remodeling. In summary, the study demonstrates that the Nkx2-5/Notch/RA signaling plays a pivotal role in macrophage differentiation from hematopoietic progenitors.

Changes in macrophage immunometabolism as a marker of skeletal muscle dysfunction across the lifespan

One of the most pronounced changes in the elderly is loss of strength and mobility due to the decline of skeletal muscle function, resulting in a multifactorial condition termed sarcopenia. Although significant clinical changes begin to manifest at advanced ages, recent studies have shown that changes at the cellular and molecular level precede the symptomatology of sarcopenia. By utilizing a single-cell transcriptomic atlas of mouse skeletal muscle across the lifespan, we identified a clear sign of immune senescence that presents during middle age. More importantly, the change in macrophage phenotype in middle age may explain the changes in extracellular matrix composition, especially collagen synthesis, that contributes to fibrosis and overall muscle weakness with advanced age. Our results show a novel paradigm whereby skeletal muscle dysfunction is driven by alterations in tissue-resident macrophages before the appearance of clinical symptoms in middle-aged mice, providing a new therapeutic approach via regulation of immunometabolism.

Studies in the Falls Efficacy Scale-International for patients with cervical compressive myelopathy: Reliability, validity, and minimum clinically important difference

CONTEXT

Patients with cervical compressive myelopathy (CCM) often complain of body balance problems, such as fear of falling and bodily unsteadiness. However, no accepted patient-reported outcome measures (PROMs) for this symptomatology exist. The Falls Efficacy Scale-International (FES-I) is one of the most widely used PROMs for evaluating impaired body balance in various clinical fields.

OBJECTIVE

To examine reliability, validity, and minimum clinically important difference (MCID) of the FES-I for the evaluation of impaired body balance in patients with CCM.

METHODS

Patients who underwent surgery for CCM were retrospectively reviewed. The FES-I was administered preoperatively and at 1 year postoperatively. Further, cJOA-LE score (subscore for lower extremities in the Japanese Orthopaedic Association score for cervical myelopathy) and stabilometric data, obtained at the same time points of the FES-I administration, were analyzed. Reliability was examined through internal consistency with Cronbach's alpha. Convergent validity was studied using correlation analysis. The MCID was estimated using anchor- and distribution-based methods.

RESULTS

Overall, 151 patients were included for analysis. Cronbach's alpha coefficient was the acceptable value of 0.97 at both baseline and 1 year postoperatively. As for convergent validity, the FES-I had significant correlations with the cJOA-LE score and stabilometric parameters both at baseline and 1 year postoperatively. The MCID calculated using anchor- and distribution-based methods was 5.5 and 10, respectively.

CONCLUSION

FES-I is a reliable and valid PROM to evaluate body balance problems for the CCM population. The established thresholds of MCID can help clinicians recognize the clinical significance of changes in patient status.

Effect of low body mass index on clinical recovery after fusion surgery for osteoporotic vertebral fracture: A retrospective, multicenter study of 237 cases

A retrospective multicenter study. Body mass index (BMI) is recognized as an important determinant of osteoporosis and spinal postoperative outcomes; however, the specific impact of BMI on surgery for osteoporotic vertebral fractures (OVFs) remains inconclusive. This retrospective multicenter study investigated the impact of BMI on clinical outcomes following fusion surgery for OVFs. 237 OVF patients (mean age, 74.3 years; 48 men and 189 women) with neurological symptoms who underwent spinal fusion were included in this study. Patients were grouped by World Health Organization BMI categories: low BMI (<18.5 kg/m2), normal BMI (≥18.5 and <25 kg/m2), and high BMI (≥25 kg/m2). Patients' backgrounds, surgical method, radiological findings, pain measurements, activities of daily living (ADL), and postoperative complications were compared after a mean follow-up period of 4 years. As results, the proportion of patients able to walk independently was significantly smaller in the low BMI group (75.0%) compared with the normal BMI group (89.9%; P = .01) and the high BMI group (94.3%; P = .04). Improvement in the visual analogue scale for leg pain was significantly less in the low BMI group than the high BMI group (26.7 vs 42.8 mm; P = .046). Radiological evaluation, the Frankel classification, and postoperative complications were not significantly different among all 3 groups. Improvement of pain intensity and ADL in the high BMI group was equivalent or non-significantly better for some outcome measures compared with the normal BMI group. Leg pain and independent walking ability after fusion surgery for patients with OVFs improved less in the low versus the high BMI group. Surgeons may want to carefully evaluate at risk low BMI patients before fusion surgery for OVF because poor clinical results may occur.

Segmental cervical instability does not drive the loss of cervical lordosis after laminoplasty in patients with cervical spondylotic myelopathy

BACKGROUND/CONTEXT

Kyphotic deformity after cervical laminoplasty (CLP) often leads to unfavorable neurological recovery due to insufficient indirect decompression of the spinal cord. Existing literature has described that segmental cervical instability is a contraindication for CLP because it is a potential risk factor for kyphotic changes after surgery; however, this has never been confirmed in any clinical studies.

PURPOSE

To confirm whether segmental cervical instability was an independent risk factor for postoperative kyphotic change and to examine whether segmental cervical instability led to poor neurological outcomes after CLP for cervical spondylotic myelopathy (CSM).

STUDY DESIGN/SETTING

A retrospective study PATIENT SAMPLE: Patients who underwent CLP for CSM between January 2013 and January 2021 with a follow-up period of ≥1 year were enrolled.

OUTCOME MEASURES

Cervical radiographic measurements including C2-C7 lordosis (C2-7 angle), cervical sagittal vertical axis, C7 slope, flexion range of motion (fROM) and extension ROM (eROM) were assessed using neutral and flexion-extension views. Segmental cervical instability was classified into anterolisthesis (AL) of ≥2 mm displacement, retrolisthesis (RL) of ≥2 mm displacement, and translational instability (TI) of ≥3 mm translational motion. The amount of C2-7 angle loss at the follow-up period compared to the preoperative measurements was defined as cervical lordosis loss (CLL). Neurological outcomes were assessed using the recovery rate of the Japanese Orthopedic Association score (JOA-RR).

METHODS

CLL was compared among patients with and without segmental cervical instability. Further, multiple linear regression model for CLL was built for the evaluation with adjustment of the reported risks, including cervical sagittal vertical axis, C7 slope, fROM, eROM, and patient age together with AL, RL, and TI, as independent variables. The JOA-RR was also compared between patients with and without segmental cervical instability.

RESULTS

A total of 138 patients (mean age, 68.7 years; 65.9% male) were included in the analysis. AL, RL, and TI were found in 12 (8.7%), 33 (23.9%), and 16 (11.6%) patients, respectively. Comparisons among the groups showed that AL led to greater CLL; however, RL and TI did not. Multiple linear regression analysis revealed that greater CLL is significantly associated with greater fROM and smaller eROM (regression coefficient [β]=0.328, 95% confidence interval: 0.178 to 0.478, p<.001; β=-0.372, 95% confidence interval: -0.591 to -0.153, p=.001, respectively). However, there were no significant statistical associations in the AL, RL, and TI. Whereas, patients with AL tended to exhibit lower JOA-RR than those without AL (37.8% vs. 52.0%, p=.108).

CONCLUSIONS

Segmental cervical instability is not the definitive driver for loss of cervical lordosis after CLP in patients with CSM; thus, is not a contraindication in and of itself. However, it is necessary to consider the indications for CLP, according to individual cases of patients with AL on baseline radiograph, which is a sign of poor neurological recovery.

A novel murine model of atrial fibrillation by diphtheria toxin-induced injury

The treatment of atrial fibrillation (AF) continues to be a significant clinical challenge. While genome-wide association studies (GWAS) are beginning to identify AF susceptibility genes (Gudbjartsson et al., Nature, 2007, 448, 353-357; Choi et al., Circ. Res., 2020, 126, 200-209; van Ouwerkerk et al., Circ. Res., 2022, 127, 229-243), non-genetic risk factors including physical, chemical, and biological environments remain the major contributors to the development of AF. However, little is known regarding how non-genetic risk factors promote the pathogenesis of AF (Weiss et al., Heart Rhythm, 2016, 13, 1868-1877; Chakraborty et al., Heart Rhythm, 2020, 17, 1,398-1,404; Nattel et al., Circ. Res., 2020, 127, 51-72). This is, in part, due to the lack of a robust and reliable animal model induced by non-genetic factors. The currently available models using rapid pacing protocols fail to generate a stable AF phenotype in rodent models, often requiring additional genetic modifications that introduce potential sources of bias (Schüttler et al., Circ. Res., 2020, 127, 91-110). Here, we report a novel murine model of AF using an inducible and tissue-specific activation of diphtheria toxin (DT)-mediated cellular injury system. By the tissue-specific and inducible expression of human HB-EGF in atrial myocytes, we developed a reliable, robust and scalable murine model of AF that is triggered by a non-genetic inducer without the need for AF susceptibility gene mutations.

NanoSPECT imaging reveals the uptake of 123I-labeled oxidized low-density lipoprotein in the brown adipose tissue of mice via CD36

AIMS

The liver is the major organ shown to remove oxidized low-density lipoprotein (oxLDL) from the circulation. Given increased evidence that thermogenic adipose tissue has anti-atherogenic effects, we used 123I-labeled oxLDL as a tracer to reveal oxLDL accumulation in the brown adipose tissue (BAT) of mice. We also explored the mechanisms of oxLDL accumulation in BAT.

METHODS AND RESULTS

We used high-resolution nanoSPECT/CT to investigate the tissue distribution of 123I-oxLDL and 123I-LDL (control) following intravenous injection into conscious mice. 123I-oxLDL distribution was discovered in BAT at an intensity equivalent to that in the liver, whereas 123I-LDL was detected mostly in the liver. Consistent with the function of BAT related to sympathetic nerve activity, administering anesthesia in mice almost completely eliminated the accumulation of 123I-oxLDL in BAT, and this effect was reversed by administering β3-agonist. Furthermore, exposing mice to cold stress at 4 °C enhanced 123I-oxLDL accumulation in BAT. Because in 123I-oxLDL, the protein of oxLDL was labeled, we performed additional experiments with DiI-oxLDL in which the lipid phase of oxLDL was fluorescently labeled and observed similar results, suggesting that the whole oxLDL particle was taken up by BAT. To identify the receptor responsible for oxLDL uptake in BAT, we analyzed the expression of known oxLDL receptors (e.g., SR-A, CD36, LOX-1) in cultured brown adipocyte cell line and primary brown adipocytes and found that CD36 was the major receptor expressed. Treatment of cells with CD36 siRNA or CD36 neutralizing antibody significantly inhibited DiI-oxLDL uptake. Finally, CD36 deletion in mice abolished the accumulation of 123I-oxLDL and DiI-oxLDL in BAT, indicating that CD36 is the major receptor for oxLDL in BAT.

CONCLUSION

We show novel evidence for the CD36-mediated accumulation of oxLDL in BAT, suggesting that BAT may exert its anti-atherogenic effects by removing atherogenic LDL from the circulation.

A Collaborative Study on the Classification of Silicone Oil Droplets and Protein Particles Using Flow Imaging Method

In this study, we conducted a collaborative study on the classification between silicone oil droplets and protein particles detected using the flow imaging (FI) method toward proposing a standardized classifier/model. We compared four approaches, including a classification filter composed of particle characteristic parameters, principal component analysis, decision tree, and convolutional neural network in the performance of the developed classifier/model. Finally, the points to be considered were summarized for measurement using the FI method, and for establishing the classifier/model using machine learning to differentiate silicone oil droplets and protein particles.

Pacemaker translocations and power laws in 2D stem cell-derived cardiomyocyte cultures

Power laws are of interest to several scientific disciplines because they can provide important information about the underlying dynamics (e.g. scale invariance and self-similarity) of a given system. Because power laws are of increasing interest to the cardiac sciences as potential indicators of cardiac dysfunction, it is essential that rigorous, standardized analytical methods are employed in the evaluation of power laws. This study compares the methods currently used in the fields of condensed matter physics, geoscience, neuroscience, and cardiology in order to provide a robust analytical framework for evaluating power laws in stem cell-derived cardiomyocyte cultures. One potential power law-obeying phenomenon observed in these cultures is pacemaker translocations, or the spatial and temporal instability of the pacemaker region, in a 2D cell culture. Power law analysis of translocation data was performed using increasingly rigorous methods in order to illustrate how differences in analytical robustness can result in misleading power law interpretations. Non-robust methods concluded that pacemaker translocations adhere to a power law while robust methods convincingly demonstrated that they obey a doubly truncated power law. The results of this study highlight the importance of employing comprehensive methods during power law analysis of cardiomyocyte cultures.

The Effects of Surgery on Postural Instability in Patients With Cervical Compressive Myelopathy: Evaluating Subjective Perceptions and Objective Measurements

STUDY DESIGN

A retrospective study.

OBJECTIVE

To investigate the effects of surgery on the subjective perception of bodily unsteadiness and the objective measurements of postural instability in patients with cervical compressive myelopathy (CCM).

SUMMARY OF BACKGROUND DATA

Several studies have demonstrated that CCM patients have impaired postural stability and investigated its surgical outcomes. However, these studies have only objectively measured postural stability by using a stabilometer or three-dimensional motion capture system. There have been no studies examining the subjective perception of postural instability in CCM patients.

MATERIALS AND METHODS

We retrospectively reviewed patients who underwent decompressive surgery for CCM. The Fall Efficacy Scale-International (FES-I) and a self-prepared questionnaire were used to evaluate subjective perception of bodily unsteadiness. To objectively assess postural instability, a stabilometric analysis was performed with the following parameters: sway area (SwA, cm2), sway velocity (SwV, cm/s), and sway density (SwD, /cm). The evaluations were performed preoperatively, during the early postoperative period (3-6 mo postoperatively), and at 1-year postoperatively in patients with CCM. The evaluation results were compared with age-matched, sex-matched, and body mass index-matched healthy subjects.

RESULTS

We included 70 CCM patients and 36 healthy subjects in this study. In both the FES-I and self-prepared questionnaire, CCM patients reported significantly milder postoperative bodily unsteadiness. The stabilometric parameters were significantly improved during the postoperative period when compared with preoperative values. Nevertheless, neither the self-reported outcome measures nor stabilometric parameters of CCM patients reached the levels of those in healthy controls in the postoperative period.

CONCLUSION

This was the first study to examine CCM surgical outcomes in terms of both subjective perception and objective postural instability. While both objective postural stability and subjective perception improved following decompressive surgery, they did not reach the levels seen in healthy participants.

LEVEL OF EVIDENCE

Level III.

Usefulness of Percutaneous Ultrasonography for Deciding the Need of Surgical Evacuation of Epidural Hematoma After Cervical Double-door Laminoplasty

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

The objective of this study was to investigate the diagnostic utility of percutaneous ultrasonography (PUS) for postoperative epidural hematoma (EH) as a postoperative complication.

SUMMARY OF BACKGROUND DATA

We investigated the usefulness of PUS for determining the need of surgical evacuation of postoperative EH by comparing the postoperative magnetic resonance imaging (MRI) and PUS of the spinal cord.

MATERIALS AND METHODS

This study included patients who underwent cervical laminoplasty using suture anchors. Regular MRI and PUS were performed 1 week postoperatively. Whenever the patients exhibited neurological deterioration, MRI and PUS were performed. The spinal cord decompression status was classified into 3 grades using MRI and PUS. The existence of spinal pulsation was determined by PUS.

RESULTS

One hundred thirty-one patients were investigated. The decompression status by MRI and PUS, and the pulsation status by PUS showed a correlation with neurological deterioration (P<0.001). Four cases showed postoperative neurological deterioration and required revision surgery. The decompression status in these cases was classified as "poor" by both MRI and PUS, and as "no-pulsation" by PUS pulsation. The sensitivity and specificity for neurological deterioration was 100% and 95.1% in MRI decompression, 100% and 92.9% in PUS decompression, and 100% and 99.2% in PUS pulsation, respectively.

CONCLUSIONS

This is the first report that the disappearance of spinal pulsation was associated with neurological deterioration. PUS was useful in determining the need of surgical evacuation for postoperative EH. PUS should be the first choice of examination in the event of postoperative neurological deterioration following a cervical laminoplasty. When the disappearance of pulsation is confirmed, an additional hematoma evacuation surgery should be considered immediately without undertaking MRI.

LEVEL OF EVIDENCE

Level III.

Recessive ciliopathy mutations in primary endocardial fibroelastosis: a rare neonatal cardiomyopathy in a case of Alstrom syndrome

Abstract

Among neonatal cardiomyopathies, primary endocardial fibroelastosis (pEFE) remains a mysterious disease of the endomyocardium that is poorly genetically characterized, affecting 1/5000 live births and accounting for 25% of the entire pediatric dilated cardiomyopathy (DCM) with a devastating course and grave prognosis. To investigate the potential genetic contribution to pEFE, we performed integrative genomic analysis, using whole exome sequencing (WES) and RNA-seq in a female infant with confirmed pathological diagnosis of pEFE. Within regions of homozygosity in the proband genome, WES analysis revealed novel parent-transmitted homozygous mutations affecting three genes with known roles in cilia assembly or function. Among them, a novel homozygous variant [c.1943delA] of uncertain significance in ALMS1 was prioritized for functional genomic and mechanistic analysis. Loss of function mutations of ALMS1 have been implicated in Alstrom syndrome (AS) [OMIM 203800], a rare recessive ciliopathy that has been associated with cardiomyopathy. The variant of interest results in a frameshift introducing a premature stop codon. RNA-seq of the proband’s dermal fibroblasts confirmed the impact of the novel ALMS1 variant on RNA-seq reads and revealed dysregulated cellular signaling and function, including the induction of epithelial mesenchymal transition (EMT) and activation of TGFβ signaling. ALMS1 loss enhanced cellular migration in patient fibroblasts as well as neonatal cardiac fibroblasts, while ALMS1-depleted cardiomyocytes exhibited enhanced proliferation activity. Herein, we present the unique pathological features of pEFE compared to DCM and utilize integrated genomic analysis to elucidate the molecular impact of a novel mutation in ALMS1 gene in an AS case. Our report provides insights into pEFE etiology and suggests, for the first time to our knowledge, ciliopathy as a potential underlying mechanism for this poorly understood and incurable form of neonatal cardiomyopathy.

Key message

Primary endocardial fibroelastosis (pEFE) is a rare form of neonatal cardiomyopathy that occurs in 1/5000 live births with significant consequences but unknown etiology.

Integrated genomics analysis (whole exome sequencing and RNA sequencing) elucidates novel genetic contribution to pEFE etiology.

In this case, the cardiac manifestation in Alstrom syndrome is pEFE. To our knowledge, this report provides the first evidence linking ciliopathy to pEFE etiology.

Infants with pEFE should be examined for syndromic features of Alstrom syndrome.

Our findings lead to a better understanding of the molecular mechanisms of pEFE, paving the way to potential diagnostic and therapeutic applications.

Supplementary information

The online version contains supplementary material available at 10.1007/s00109-021-02112-z.

Impact of morphological restoration of the spinal cord from the preoperative to early postoperative periods on C5 palsy development

OBJECTIVE

C5 palsy (C5P) is a known complication of cervical decompression surgery. The tethering effect of the C5 nerve root following the posterior shift of the spinal cord is the most accepted pathologic mechanism for C5P development; however, this mechanism cannot fully explain C5P by itself in clinical practice. Separately, some studies have suggested that preoperative severe spinal cord compression and postoperative morphological changes in the spinal cord affect C5P development; however, no previous study has quantitatively addressed these possibilities. The aim of this study was to examine whether spinal cord morphology and morphological restoration after surgery affect C5P development.

METHODS

The authors reviewed consecutive patients with degenerative cervical myelopathy who underwent laminoplasty including the C3-4 and C4-5 intervertebral disc levels. All participants underwent MRI both preoperatively and within 4 weeks postoperatively. To assess the severity of spinal cord compression, the compression ratio (CR; spinal cord sagittal diameter/transverse diameter) was calculated. As an index of morphological changes in the spinal cord during the early postoperative period, the change rate of CR (CrCR, %) was calculated as CRwithin 4 weeks postoperatively/CRpreoperatively × 100. These measurements were performed at both the C3-4 and C4-5 intervertebral disc levels. The study cohort was divided into C5P and non-C5P (NC5P) groups; then, CR and CrCR, in addition to other radiographic variables associated with C5P development, were compared between the groups.

RESULTS

A total of 114 patients (mean age 67.6 years, 58.8% men) were included in the study, with 5 and 109 patients in the C5P and NC5P groups, respectively. Preoperative CR at both the C3-4 and C4-5 levels was significantly lower in the C5P group than in the NC5P group (0.35 vs 0.44, p = 0.042 and 0.27 vs 0.39, p = 0.021, respectively). Patients with C5P exhibited significantly higher CrCR at the C3-4 level than those without (139.3% vs 119.0%, p = 0.046), but the same finding was not noted for CrCR at the C4-5 level. There were no significant differences in other variables between the groups.

CONCLUSIONS

This study reveals that severe compression of the spinal cord and its greater morphological restoration during the early postoperative period affect C5P development. These findings could support the involvement of segmental cord disorder theory, characterized as the reperfusion phenomenon, in the pathomechanism of C5P, in addition to the tethering effect.

Cardiac rehabilitation for patients with heart failure: a national Danish register-based study of predictors of referral and outcomes

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): The Danish Heart Foundation

Background

 Heart failure (HF) places a large burden on patients and society as a major cause of morbidity, mortality and healthcare costs. Participation in exercise-based cardiac rehabilitation (CR) in people with HF is a clinically and cost-effective strategy and recommended in international clinical guidelines.

Purpose

The aims of this study were to: (1) examine the temporal trends and predictors of national CR referral, and (2) compare the risk of hospital readmission and mortality in those referred for CR compared to no referral.

Methods

All patients in Denmark with incident HF were identified by the Danish Heart Failure Register in the period 2010 to 2018 (n = 33,257) and CR referral assessed within 120 days of hospital admission. Multivariable logistic regression models were used to evaluate the association between CR referral and predictors and to compare risk of hospital readmission and mortality until 1 year between referred and not referred patients.

Results

Overall, 45.0% of HF patients were referred to exercise-based CR, increasing from 31.7% in 2010 to 52.2% in 2018. Factors independently associated with higher CR referral were: NYHA functional class II, LVEF &lt;50%, diagnosis of myocardial infarction and use of ACE inhibitor. Male gender, older age, region, unemployment, retirement, living alone, non-Danish ethnic origin, lower educational level, NYHA class IV, treatment for hypertension, existing chronic obstructive lung disease and stroke were associated with lower CR referral. CR referral was associated with lower risk of readmission (adjusted odds ratio: 0.90;95%CI: 0.85-0.95), HF-specific mortality (0.61; 0.39-0.95) and all-cause mortality (0.61; 0.55-0.69) as compared to no referral.

Conclusions

Although CR referral has increased over time, only some 1 in 2 diagnosed HF patients in Denmark are referred to exercise-based CR. CR referral is associated with lower risk in readmissions and mortality. Strategies to promote CR referral including healthcare professional education on the benefits of CR and alternative methods of CR delivery are urgently needed to improve access to CR, especially for high-risk groups.

The role of glucose in physiological and pathological heart formation

Cells display distinct metabolic characteristics depending on its differentiation stage. The fuel type of the cells serves not only as a source of energy but also as a driver of differentiation. Glucose, the primary nutrient to the cells, is a critical regulator of rapidly growing embryos. This metabolic change is a consequence as well as a cause of changes in genetic program. Disturbance of fetal glucose metabolism such as in diabetic pregnancy is associated with congenital heart disease. In utero hyperglycemia impacts the left-right axis establishment, migration of cardiac neural crest cells, conotruncal formation and mesenchymal formation of the cardiac cushion during early embryogenesis and causes cardiac hypertrophy in late fetal stages. In this review, we focus on the role of glucose in cardiogenesis and the molecular mechanisms underlying heart diseases associated with hyperglycemia.

ETS-dependent enhancers for endothelial-specific expression of serum/glucocorticoid-regulated kinase 1 during mouse embryo development

Serum/glucocorticoid-regulated kinase 1 (SGK1) is predominantly expressed in endothelial cells of mouse embryos, and Sgk1 null mice show embryonic lethality due to impaired vascular formation. However, how the SGK1 expression is controlled in developing vasculature remains unknown. In this study, we first identified a proximal endothelial enhancer through lacZ reporter mouse analyses. The mouse Sgk1 proximal enhancer was narrowed down to the 5' region of the major transcription initiation site, while a human corresponding region possessed relatively weak activity. We then searched for distal enhancer candidates using in silico analyses of publicly available databases for DNase accessibility, RNA polymerase association and chromatin modification. A region approximately 500 kb distant from the human SGK1 gene was conserved in the mouse, and the mouse and human genomic fragments drove transcription restricted to embryonic endothelial cells. Minimal fragments of both proximal and distal enhancers had consensus binding elements for the ETS transcription factors, which were essential for the responsiveness to ERG, FLI1 and ETS1 proteins in luciferase assays and the endothelial lacZ reporter expression in mouse embryos. These results suggest that endothelial SGK1 expression in embryonic vasculature is maintained through at least two ETS-regulated enhancers located in the proximal and distal regions.

Hidden coexisting pathology diagnosed after cervical surgery in patients with degenerative cervical myelopathy or myeloradiculopathy: A case series report

Many neurological disorders can present similar symptomatology to degenerative cervical myelopathy (DCM) or myeloradiculopathy (DCMR). Therefore, to avoid misdiagnosis, it is important to recognise the differential diagnosis, which has been well described in previous literature. Additionally, DCM or DCMR can also coexist with other diseases that overlap some of its clinical manifestations, which may be overlooked before cervical surgery. Nevertheless, few studies have addressed this clinical situation. In clinical practice, the diagnosis of coexisting disease with DCM or DCMR would be typically made when some symptoms persist without improvement after cervical surgery. To inform the patients of this possibility preoperatively and arrive at the early diagnosis during the postoperative period, some knowledge of the possible coexisting diseases would be necessary. In this report, we reviewed 230 patients who underwent surgery for DCM or DCMR in an academic centre to examine the prevalence and kind of underlying disease that was overlooked preoperatively. The coexisting diseases relevant to their baseline symptoms were diagnosed only after cervical surgery in three patients (1.3%) and included amyotrophic lateral sclerosis, lung cancer and polymyalgia rheumatica. The overlapping symptoms were gait difficulty, scapular pain and neck pain, respectively. Surgeons should recognise that the coexisting disease with DCM or DCMR may be overlooked before cervical surgery because of overlapping symptomatology, although its prevalence is not certainly high. Further, when the specific symptom persisted without improvement after surgery for DCM or DCMR, the patient should be comprehensively examined, considering diverse pathological conditions, not only neurological disorders.

Gap between flexion and extension ranges of motion: a novel indicator to predict the loss of cervical lordosis after laminoplasty in patients with cervical spondylotic myelopathy

OBJECTIVE

Kyphotic deformity resulting from the loss of cervical lordosis (CL) is a rare but serious complication after cervical laminoplasty (CLP), and it is essential to recognize the risk factors. Previous studies have demonstrated that a greater flexion range of motion (fROM) and smaller extension ROM (eROM) in the cervical spine are associated with the loss of CL after CLP. Considering these facts together, one can hypothesize that an indicator representing the gap between fROM and eROM (gROM) is highly useful in predicting postoperative CL loss. In the present study, the authors aimed to investigate the risk factors of marked CL loss after CLP for cervical spondylotic myelopathy (CSM), including the gROM as a potential predictor.

METHODS

Patients who had undergone CLP for CSM were divided into those with and those without a loss of more than 10° in the sagittal Cobb angle between C2 and C7 at the final follow-up period compared to preoperative measurements (CL loss [CLL] group and no CLL [NCLL] group, respectively). Demographic characteristics, surgical information, preoperative radiographic measurements, and posterior paraspinal muscle morphology evaluated with MRI were compared between the two groups. fROM and eROM were examined on neutral and flexion-extension views of lateral radiography, and gROM was calculated using the following formula: gROM (°) = fROM - eROM. The performance of variables in discriminating between the CLL and NCLL groups was assessed using the receiver operating characteristic (ROC) curve.

RESULTS

This study included 111 patients (mean age at surgery 68.3 years, 61.3% male), with 10 and 101 patients in the CLL and NCLL groups, respectively. Univariate analyses showed that fROM and gROM were significantly greater in the CLL group than in the NCLL group (40.2° vs 26.6°, p < 0.001; 31.6° vs 14.3°, p < 0.001, respectively). ROC curve analyses revealed that both fROM and gROM had excellent discriminating capacities; gROM was likely to have a higher area under the ROC curve than fROM (0.906 vs 0.860, p = 0.094), with an optimal cutoff value of 27°.

CONCLUSIONS

The gROM is a highly useful indicator for predicting a marked loss of CL after CLP. For CSM patients with a preoperative gROM exceeding 30°, CLP should be carefully considered, since kyphotic changes can develop postoperatively.

GLUT1 overexpression enhances glucose metabolism and promotes neonatal heart regeneration

The mammalian heart switches its main metabolic substrate from glucose to fatty acids shortly after birth. This metabolic switch coincides with the loss of regenerative capacity in the heart. However, it is unknown whether glucose metabolism regulates heart regeneration. Here, we report that glucose metabolism is a determinant of regenerative capacity in the neonatal mammalian heart. Cardiac-specific overexpression of Glut1, the embryonic form of constitutively active glucose transporter, resulted in an increase in glucose uptake and concomitant accumulation of glycogen storage in postnatal heart. Upon cryoinjury, Glut1 transgenic hearts showed higher regenerative capacity with less fibrosis than non-transgenic control hearts. Interestingly, flow cytometry analysis revealed two distinct populations of ventricular cardiomyocytes: Tnnt2-high and Tnnt2-low cardiomyocytes, the latter of which showed significantly higher mitotic activity in response to high intracellular glucose in Glut1 transgenic hearts. Metabolic profiling shows that Glut1-transgenic hearts have a significant increase in the glucose metabolites including nucleotides upon injury. Inhibition of the nucleotide biosynthesis abrogated the regenerative advantage of high intra-cardiomyocyte glucose level, suggesting that the glucose enhances the cardiomyocyte regeneration through the supply of nucleotides. Our data suggest that the increase in glucose metabolism promotes cardiac regeneration in neonatal mouse heart.

Preoperative Cyst Formation as a Predictive Feature of Spontaneous Regression of Retro-Odontoid Pseudotumor After Posterior Fusion

OBJECTIVE

Although the spontaneous regression of pseudotumors after posterior fusion has been reported, the predictive factors remain unclear. We examined the radiological features that predict for the regression of retro-odontoid pseudotumors after posterior fusion, with a specific focus on cyst formation.

METHODS

We included 28 patients with a diagnosis of retro-odontoid pseudotumor using preoperative magnetic resonance imaging. The radiographic parameters and pseudotumor thickness were measured pre- and postoperatively. The regression rate for each pseudotumor was calculated. The presence of a cyst around the retro-odontoid pseudotumor was investigated. If present, the cyst thickness was measured. To elucidate the predictors for the postoperative regression of pseudotumors, the patients were divided into 2 cohorts: the regression group with a regression rate >40% and the no-regression group with a regression rate of <40%. Multivariate logistic regression analysis, including the demographic data and preoperative radiographic parameters as independent variables, was performed.

RESULTS

The mean pseudotumor size had decreased significantly from 8.8 ± 3.6 mm preoperatively to 5.3 ± 2.0 mm postoperatively (P < 0.0001). The mean regression rate was 35.9% during a magnetic resonance imaging follow-up period of 8.6 months (range, 6-12 months). Cystic lesions were noted in 10 patients (35.7%) preoperatively. The mean cyst size was 4.7 ± 1.9 mm. All cysts were located dorsal to the pseudotumors and were involved at the maximum spinal compression levels. Nevertheless, all the cysts had disappeared postoperatively. Multivariate logistic regression analysis revealed that the pseudotumor regression group had had a significantly greater proportion of cysts (57.1% vs. 14.3%; odds ratio, 11.7; P = 0.013).

CONCLUSIONS

The presence of cystic lesions protruding from retro-odontoid pseudotumors might serve as a predictive factor for the spontaneous regression of pseudotumors after posterior fusion.

Biologic Agents Preserve the C-2 Pedicle in Patients with Rheumatoid Arthritis: A Comparative Imaging Study Using Three-Dimensional Computed Tomography

OBJECTIVE

To investigate whether biologic agents (BAs) reduce a narrow C-2 pedicle screw trajectory, which is often a key stabilizer in surgical treatment, in patients with rheumatoid arthritis (RA).

METHODS

A total of 100 patients with RA treated with and without BAs (BA [+] group [n = 50] and BA [-] group [n = 50]), respectively, were included in the present study. Computed tomography (CT) images of their cervical spine, including C-2, were analyzed. The maximum screw diameter at C-2 that could be inserted without breaching the cortex, measured on 3-dimensional images using a CT-based navigation system, was compared between the groups with and without BA administration. Furthermore, the destruction of the atlantoaxial joint was examined using CT images. The risk factors for a narrow C-2 pedicle were elucidated among the patients treated with BAs.

RESULTS

The pedicle in the BA (+) group had a significantly larger C-2 maximum screw diameter than the BA (-) group (6.00 mm vs. 5.13 mm, P < 0.001), with less destruction of the atlantoaxial joint. Among the BA (+) group, a longer period until the initial administration of BAs and RA disease duration were associated with a narrow C-2 pedicle.

CONCLUSIONS

This study suggests that BAs can maintain the trajectory for C-2 pedicle screws, which acts as a key stabilizer in surgical management for the rheumatoid cervical spine, by halting the destruction of the atlantoaxial joint. Early introduction of BAs can be especially important to prevent the narrowing of the C-2 pedicle.

Importance of endothelial Hey1 expression for thoracic great vessel development and its distal enhancer for Notch-dependent endothelial transcription

Thoracic great vessels such as the aorta and subclavian arteries are formed through dynamic remodeling of embryonic pharyngeal arch arteries (PAAs). Previous work has shown that loss of a basic helix-loop-helix transcription factor Hey1 in mice causes abnormal fourth PAA development and lethal great vessel anomalies resembling congenital malformations in humans. However, how Hey1 mediates vascular formation remains unclear. In this study, we revealed that Hey1 in vascular endothelial cells, but not in smooth muscle cells, played essential roles for PAA development and great vessel morphogenesis in mouse embryos. Tek-Cre-mediated Hey1 deletion in endothelial cells affected endothelial tube formation and smooth muscle differentiation in embryonic fourth PAAs and resulted in interruption of the aortic arch and other great vessel malformations. Cell specificity and signal responsiveness of Hey1 expression were controlled through multiple cis-regulatory regions. We found two distal genomic regions that had enhancer activity in endothelial cells and in the pharyngeal epithelium and somites, respectively. The novel endothelial enhancer was conserved across species and was specific to large-caliber arteries. Its transcriptional activity was regulated by Notch signaling in vitro and in vivo, but not by ALK1 signaling and other transcription factors implicated in endothelial cell specificity. The distal endothelial enhancer was not essential for basal Hey1 expression in mouse embryos but may likely serve for Notch-dependent transcriptional control in endothelial cells together with the proximal regulatory region. These findings help in understanding the significance and regulation of endothelial Hey1 as a mediator of multiple signaling pathways in embryonic vascular formation.

Comparison of the Pharmacokinetics of RIPK1 Inhibitor GSK2982772 in Healthy Western and Japanese Subjects

Background and Objectives

GSK2982772 is an oral small-molecule RIPK1 inhibitor with potential therapeutic efficacy in immune-mediated inflammatory diseases (IMIDs). An inter-ethnic comparison of GSK2982772 pharmacokinetics was conducted based on data from Western (Study 1) and Japanese subjects (Study 2).

Methods

Both studies were single-centre, randomised, double-blind, placebo-controlled studies with objectives to assess the safety and characterise the pharmacokinetics of GSK2982772. Western subjects in Study 1 (NCT03305419), Part A (N = 15), were randomly assigned to receive 120 mg three times daily (TID), 240 mg TID, or 360 mg twice daily (BID) doses of GSK2982772, or placebo (TID or BID) for 1 day. Part B subjects (N = 47) received GSK2982772 120 mg TID, 240 mg TID, or placebo TID for 14 days. Japanese subjects in Study 2 (N = 13) (NCT03590613) were randomly assigned to receive TID doses of GSK2982772 60, 120, 240 mg TID or placebo TID for 1 day.

Results

GSK2982772 was well tolerated and adverse events were generally mild. Maximum observed plasma drug concentration (C_max), time to reach C_max (T_max), area under the plasma drug concentration versus time curve after the first GSK2982772 dose (AUC_(0–7)) of 120 and 240 mg, and (AUC_(0–24)) values for the 120 and 240 mg TID doses over a single day were similar in Japanese and Western subjects.

Conclusions

The pharmacokinetics and tolerability of GSK2982772 were similar between Western and Japanese subjects, justifying inclusion of Japanese subjects in future global clinical studies to assess the therapeutic potential of RIPK1 inhibition for the treatment of IMIDs.

Clinical Trials: NCT03305419 and NCT03590613 available from http://www.clinicaltrials.gov.

Electronic supplementary material

The online version of this article (10.1007/s13318-020-00652-2) contains supplementary material, which is available to authorized users.

Short- versus long-segment posterior spinal fusion with vertebroplasty for osteoporotic vertebral collapse with neurological impairment in thoracolumbar spine: a multicenter study

Background

Vertebroplasty with posterior spinal fusion (VP + PSF) is one of the most widely accepted surgical techniques for treating osteoporotic vertebral collapse (OVC). Nevertheless, the effect of the extent of fusion on surgical outcomes remains to be established. This study aimed to evaluate the surgical outcomes of short- versus long-segment VP + PSF for OVC with neurological impairment in thoracolumbar spine.

Methods

We retrospectively collected data from 133 patients (median age, 77 years; 42 men and 91 women) from 27 university hospitals and their affiliated hospitals. We divided patients into two groups: a short-segment fusion group (S group) with 2- or 3-segment fusion (87 patients) and a long-segment fusion group (L group) with 4- through 6-segment fusion (46 patients). Surgical invasion, clinical outcomes, local kyphosis angle (LKA), and complications were evaluated.

Results

No significant differences between the two groups were observed in terms of neurological recovery, pain scale scores, and complications. Surgical time was shorter and blood loss was less in the S group, whereas LKA at the final follow-up and correction loss were superior in the L group.

Conclusion

Although less invasiveness and validity of pain and neurological relief are secured by short-segment VP + PSF, surgeons should be cautious regarding correction loss.

Effect of bisphosphonates or teriparatide on mechanical complications after posterior instrumented fusion for osteoporotic vertebral fracture: a multi-center retrospective study

Background

The optimal treatment of osteoporosis after reconstruction surgery for osteoporotic vertebral fractures (OVF) remains unclear. In this multicentre retrospective study, we investigated the effects of typically used agents for osteoporosis, namely, bisphosphonates (BP) and teriparatide (TP), on surgical results in patients with osteoporotic vertebral fractures.

Methods

Retrospectively registered data were collected from 27 universities and affiliated hospitals in Japan. We compared the effects of BP vs TP on postoperative mechanical complication rates, implant-related reoperation rates, and clinical outcomes in patients who underwent posterior instrumented fusion for OVF. Data were analysed according to whether the osteoporosis was primary or glucocorticoid-induced.

Results

A total of 159 patients who underwent posterior instrumented fusion for OVF were included. The overall mechanical complication rate was significantly lower in the TP group than in the BP group (BP vs TP: 73.1% vs 58.2%, p = 0.045). The screw backout rate was significantly lower and the rates of new vertebral fractures and pseudoarthrosis tended to be lower in the TP group than in the BP group. However, there were no significant differences in lumbar functional scores and visual analogue scale pain scores or in implant-related reoperation rates between the two groups. The incidence of pseudoarthrosis was significantly higher in patients with glucocorticoid-induced osteoporosis (GIOP) than in those with primary osteoporosis; however, the pseudoarthrosis rate was reduced by using TP. The use of TP also tended to reduce the overall mechanical complication rate in both primary osteoporosis and GIOP.

Conclusions

The overall mechanical complication rate was lower in patients who received TP than in those who received a BP postoperatively, regardless of type of osteoporosis. The incidence of pseudoarthrosis was significantly higher in patients with GIOP, but the use of TP reduced the rate of pseudoarthrosis in GIOP patients. The use of TP was effective to reduce postoperative complications for OVF patients treated with posterior fusion.

GPCR-dependent biasing of GIRK channel signaling dynamics by RGS6 in mouse sinoatrial nodal cells

How G protein-coupled receptors (GPCRs) evoke specific biological outcomes while utilizing a limited array of G proteins and effectors is poorly understood, particularly in native cell systems. Here, we examined signaling evoked by muscarinic (M2R) and adenosine (A1R) receptor activation in the mouse sinoatrial node (SAN), the cardiac pacemaker. M2R and A1R activate a shared pool of cardiac G protein-gated inwardly rectifying K+ (GIRK) channels in SAN cells from adult mice, but A1R-GIRK responses are smaller and slower than M2R-GIRK responses. Recordings from mice lacking Regulator of G protein Signaling 6 (RGS6) revealed that RGS6 exerts a GPCR-dependent influence on GIRK-dependent signaling in SAN cells, suppressing M2R-GIRK coupling efficiency and kinetics and A1R-GIRK signaling amplitude. Fast kinetic bioluminescence resonance energy transfer assays in transfected HEK cells showed that RGS6 prefers Gαo over Gαi as a substrate for its catalytic activity and that M2R signals preferentially via Gαo, while A1R does not discriminate between inhibitory G protein isoforms. The impact of atrial/SAN-selective ablation of Gαo or Gαi2 was consistent with these findings. Gαi2 ablation had minimal impact on M2R-GIRK and A1R-GIRK signaling in SAN cells. In contrast, Gαo ablation decreased the amplitude and slowed the kinetics of M2R-GIRK responses, while enhancing the sensitivity and prolonging the deactivation rate of A1R-GIRK signaling. Collectively, our data show that differences in GPCR-G protein coupling preferences, and the Gαo substrate preference of RGS6, shape A1R- and M2R-GIRK signaling dynamics in mouse SAN cells.

Significance of flexion range of motion as a risk factor for kyphotic change after cervical laminoplasty

Kyphotic deformity is a rare but serious complication after cervical laminoplasty (CLP), and several studies have investigated its predictors. In these studies, a kyphotic Cobb angle of 0°-5° between C2 and C7 at a certain postoperative time-point was often used to detect kyphotic deformity. However, studies considering the amount of cervical lordosis loss compared to the preoperative measurement are scarce. This study aimed to elucidate risk factors for kyphotic change after CLP by comparing patients with and without marked loss of cervical lordosis postoperatively. The study population was divided into seven patients with and 92 patients without a loss of >10° of the C2-7 angle during the follow-up period compared to the preoperative measurements [cervical lordosis loss (CLL) group and no CLL (NCLL) group, respectively]; demographic characteristics, surgical information, preoperative radiographic sagittal parameters of the cervical spine, and posterior paravertebral muscle morphology evaluated by magnetic resonance imaging were compared between two groups. A univariate analysis revealed that the CLL group had significantly greater flexion range of motion (fROM) than the NCLL group (43.0° vs. 25.8°, P < 0.001); however, no statistical significance was identified for other parameters. The fROM had a high capacity to discriminate between the CLL and NCLL groups (area under the receiver-operating characteristic curve, 0.880; P < 0.001; 95% confidence interval, 0.589-0.974) with an optimal cutoff point of 37°. This study suggests that greater fROM is a risk factor for the development of kyphotic changes after CLP. For patients with preoperative fROM exceeding 40°, CLP should be carefully indicated.

Levocetirizine Oral Disintegrating Tablet: A Randomized Open-Label Crossover Bioequivalence Study in Healthy Japanese Volunteers

Levocetirizine is classified as a second‐generation antihistamine. Levocetirizine is available for the treatment of allergic disorders such as allergic rhinitis and chronic idiopathic urticaria. This was a single‐center, single‐dose, open‐label, randomized, 2‐way crossover study in healthy Japanese male subjects consisting of 2 parts. Part 1 compared the bioavailability of levocetirizine oral disintegrating tablet (ODT) and levocetirizine immediate‐release tablet (IRT) taken with water in the fasted state in 24 subjects; all subjects completed this part of the trial. In part 2, the bioavailability of levocetirizine ODT without water was compared with that of levocetirizine IRT with water in the fasted state in 48 subjects; 47 subjects completed this part of the trial. Bioequivalence was demonstrated between levocetirizine IRT 5 mg and ODT 5 mg. The safety profiles were generally similar between levocetirizine ODT and levocetirizine IRT, with no serious adverse events, deaths, or adverse events leading to withdrawal reported during the study.

The Surgical Outcomes of Spinal Fusion for Osteoporotic Vertebral Fractures in the Lower Lumbar Spine with a Neurological Deficit

Introduction

Osteoporotic vertebral fracture (OVF) is the most common osteoporotic fracture, and some patients require surgical intervention to improve their impaired activities of daily living with neurological deficits. However, many previous reports have focused on OVF around the thoracolumbar junction, and the surgical outcomes of lumbar OVF have not been thoroughly discussed. We aimed to investigate the surgical outcomes for lumbar OVF with a neurological deficit.

Methods

Patients who underwent fusion surgery for thoracolumbar OVF with a neurological deficit were enrolled at 28 institutions. Clinical information, comorbidities, perioperative complications, Japanese Orthopaedic Association scores, visual analog scale scores, and radiographic parameters were compared between patients with lower lumbar fracture (L3-5) and those with thoracolumbar junction fracture (T10-L2). Each patient with lower lumbar fracture (L group) was matched with to patients with thoracolumbar junction fracture (T group).

Results

A total 403 patients (89 males and 314 females, mean age: 73.8 ± 7.8 years, mean follow-up: 3.9 ± 1.7 years) were included in this study. Lower lumbar OVF was frequently found in patients with lower bone mineral density. After matching, mechanical failure was more frequent in the L group (L group: 64%, T group: 39%; p < 0.001). There was no difference between groups in the clinical and radiographical outcomes, although the rates of complication and revision surgery were still high in both groups.

Conclusions

The surgical intervention for OVF is effective in patients with myelopathy or radiculopathy regardless of the surgical level, although further study is required to improve clinical and radiographical outcomes.

Level of evidence

Level III

Gas containing intraspinal synovial cyst in the lumbar spine: Case report and literature review

Intraspinal synovial cyst (ISC) is a well-documented pathology. It is sometimes found in the degenerative lumbar spine and can result in neurological disorders. ISC typically contains xanthochromic fluid, blood, inflammatory tissue, and/or osseous structures, enclosed by fibrous tissue. Regarding the treatment modalities, the effectiveness of both nonsurgical management, such as oral analgesics, needle aspiration, and intra-articular injection of corticosteroid drugs, and surgical management, have been reported. Previous studies have described that the ISC can contain gas, which is derived from the vacuum phenomenon of an adjacent facet joint; however, this clinical condition has never been systematically investigated because of its rarity. In the present report, we describe the case of a 68-year-old male with gas-containing ISC in the lumbar spine who was successfully treated with surgical management; additionally, we performed a literature review to discuss the decision-making process for cases of gas-containing ISC. Based on our findings and previous literature, we recommend that considering the peculiarity of the content of such lesions in addition to the ball-valve effect of a synovial cyst, prompt transition to surgical management would be pertinent when nonsurgical treatment cannot achieve satisfactory outcomes in such cases.

Complications after spinal fixation surgery for osteoporotic vertebral collapse with neurological deficits: Japan Association of Spine Surgeons with ambition multicenter study

BACKGROUND

There have been few reports on the incidence and risk factors of the complications after spinal fixation surgery for osteoporotic vertebral collapse (OVC) with neurological deficits. This study aimed to identify the incidence and risk factors of the complications after OVC surgery.

METHODS

In this retrospective multicenter study, a total of 403 patients (314 women and 89 men; mean age 73.8 years) who underwent spinal fixation surgery for OVC with neurological deficits between 2005 and 2014 were enrolled. Data on patient demographics were collected, including age, sex, body mass index, smoking, steroid use, medical comorbidities, and surgical procedures. All postoperative complications that occurred within 6 weeks were recorded. Patients were classified into two groups, namely, complication group and no complication group, and risk factors for postoperative complications were investigated by univariate and multivariate analyses.

RESULTS

Postoperative complications occurred in 57 patients (14.1%), and the most common complication was delirium (5.7%). In the univariate analysis, the complication group was found to be older (p = 0.039) and predominantly male (p = 0.049), with higher occurrence rate of liver disease (p = 0.001) and Parkinson's disease (p = 0.039) compared with the no-complication group. In the multivariate analysis, the significant independent risk factors were age (p = 0.021; odds ratio [OR] 1.051, 95% confidence interval [CI] 1.007-1.097), liver disease (p < 0.001; OR 8.993, 95% CI 2.882-28.065), and Parkinson's disease (p = 0.009; OR 3.636, 95% CI 1.378-9.599).

CONCLUSIONS

Complications after spinal fixation surgery for OVC with neurological deficits occurred in 14.1%. Age, liver disease, and Parkinson's disease were demonstrated to be independent risk factors for postoperative complications.

Surgical outcomes of spinal fusion for osteoporotic vertebral fracture in the thoracolumbar spine: Comprehensive evaluations of 5 typical surgical fusion techniques

BACKGROUND

A consensus on the optimal surgical procedure for thoracolumbar OVF has yet to be reached due to the previous relatively small number of case series. The study was conducted to investigate surgical outcomes for osteoporotic vertebral fracture (OVF) in the thoracolumbar spine.

METHODS

In total, 315 OVF patients (mean age, 74 years; 68 men and 247 women) with neurological symptoms who underwent spinal fusion with a minimum 2-year follow-up were included. The patients were divided into 5 groups by procedure: anterior spinal fusion alone (ASF group, n = 19), anterior/posterior combined fusion (APSF group, n = 27), posterior spinal fusion alone (PSF group, n = 40), PSF with 3-column osteotomy (3CO group, n = 92), and PSF with vertebroplasty (VP + PSF group, n = 137).

RESULTS

Mean operation time was longer in the APSF group (p < 0.05), and intraoperative blood loss was lower in the VP + PSF group (p < 0.05). The amount of local kyphosis correction was greater in the APSF and 3CO groups (p < 0.05). Clinical outcomes were approximately equivalent among all groups.

CONCLUSION

All 5 procedures resulted in acceptable neurological outcomes and functional improvement in walking ability. Moreover, they were similar with regard to complication rates, prevalence of mechanical failure related to the instrumentation, and subsequent vertebral fracture. Individual surgical techniques can be adapted to suit patient condition or severity of OVF.

Assessing the Intraoperative Risk of Esophageal Perforation during Anterior Cervical Spine Surgery: A Study Using Intraoperative Computed Tomography

Introduction

Using intraoperative computed tomography (iCT), we aimed to clarify the course of the esophagus and pharynx during anterior cervical spine surgery to estimate the risk of intraoperative injury.

Methods

Sixteen patients who underwent anterior cervical spine surgery with intraoperative CT for registration of a navigation system without release of blade retraction were included. To investigate the status of the retracted esophagus and pharynx, the distance between the nasogastric tube and center of the vertebra (NVD) was measured at each disc and vertebral level (C4-7) using axial CT. The location of the cricoid cartilage, which may affect the shift of the esophagus and pharynx, was noted. Presence or absence of contact between the esophagus and the edge of the surgical blade was investigated.

Results

The NVDs were 28.0, 28.3, 28.9, 27.2, 24.7, 19.9, and 13.8 mm at C4, C4/5, C5, C5/6, C6, C6/7, and C7, respectively; NVDs at C6/7 or more caudal levels were significantly shorter than those at C6 or more cranial levels (P < 0.001). The cricoid cartilage was observed at the C4-C5/6 level. Esophageal contact with the edge of the blade was observed in nine cases at C6 or more caudal levels.

Conclusions

The esophagus, which was placed at C6 or more caudal levels, was directly retracted by the blade. Nevertheless, the pharynx, which was placed at C6 or more cranial levels, was mostly retracted with the cricoid cartilage. Thus, the risk of direct esophageal injury was higher at C6 or more caudal levels than at cranial levels.

Safety and Efficacy of Ambrisentan-Phosphodiesterase Type 5 (PDE5) Inhibitor Combination Therapy for Japanese Pulmonary Arterial Hypertension Patients in Real-World Clinical Practice

Background: This retrospective study was conducted to evaluate the safety and efficacy of ambrisentan combination therapy with phosphodiesterase type 5 (PDE5) inhibitors in Japanese patients with pulmonary arterial hypertension (PAH).

Methods and Results: PAH patients who received ambrisentan for the first time in combination with a PDE5 inhibitor between January 2013 and the end of August 2015 were included in this study. Adverse drug reaction (ADR) safety analysis, as well as the efficacy analysis focusing on changes in clinical parameters, were investigated for overall cases and cases stratified by patient background. Forty-eight consecutive patients (n=21, 43.8% with idiopathic PAH; male/female, 18/30; average age, 43.3±17.4 years; World Health Organization functional class III/IV, n=22, 45.8%) who were treated with ambrisentan and a PDE5 inhibitor in Japan underwent the safety analysis. A total of 14 ADR occurred in 10 patients (20.8%). ADR included headache (8.3%), face edema (4.2%), angina pectoris (2.1%), hyperemia (2.1%), dyspnea (2.1%), pulmonary hypertension (i.e., worsening of PAH, 2.1%), nausea (2.1%), hepatic function abnormal (2.1%), edema (2.1%), and sudden death (2.1%). On analysis of hemodynamics parameters, there was a significant improvement in the mean pulmonary arterial pressure (−13.5 mmHg, P=0.0001) and pulmonary vascular resistance (−563.53 dyn·s·cm⁻⁵, P=0.0033).

Conclusions: Ambrisentan combination therapy is safe and effective in hemodynamics improvement.