Does vacuum phenomenon at non-fused discs affect the postoperative course after transforaminal lumbar interbody fusion in patients showing a positive value of difference in lumbar lordosis?

INTRODUCTION

Preoperative difference in lumbar lordosis (DiLL) was associated with surgical outcomes after single-level transforaminal lumbar interbody fusion (TLIF). Patients with DiLL>0 (DiLL (+)) tended to show worse clinical outcomes and postoperative greater restoration of lumbar lordosis (LL). However, some patients with DiLL (+) showed relatively good outcomes and no postoperative LL restration. This study aimed to elucidate whether the lumbar intervertebral disc vacuum phenomenon (VP) influences clinical course after single-level TLIF in patients with DiLL (+) and DiLL (-).

METHODS

Patients with lumbar spinal stenosis and degenerative spondylolisthesis treated with single-level TLIF were included. Pre- and postoperative LL were measured, and postoperative LL improvement was calculated. Preoperative DiLL was calculated as preoperative supine LL minus standing LL. Severity of VP at the non-fused discs (SVP (non-FS)) was evaluated using preoperative reconstructed computed tomography imaging. Clinical outcomes were assessed using the Oswestry disability index, visual analogue scale (VAS; low back pain (LBP), lower-extremity pain, numbness, and the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire. Patients were stratified by the median preoperative SVP (non-FS) score into severe and mild VP groups in patients with DiLL (+) or DiLL (-), and their surgical outcomes were compared.

RESULTS

Overall, 89 patients were included. In patients with DiLL (+) (n = 37), patients with severe VP showed worse clinical outcomes, particulary for LBP and DiLL (+) patients with mild VP showed greater LL improvement (6.5° ± 10.0°). In patients with DiLL(-) (n = 52), patients with severe VP showed worse clinical outcomes, particularly for LBP and no differences in preoperative, postoperative, and improvement of LL were observed between two groups.

CONCLUSION

Patients with DiLL (+) and DiLL (-) showed different clinical courses depending on VP severity at the non-fused discs after single-level TLIF.

Simultaneous determination of five carbapenems, highly polar antibiotics, in milk by LC-MS/MS

The simultaneous determination of five carbapenems (biapenem, doripenem, ertapenem, imipenem, and meropenem) in raw and pasteurised bovine milk samples using LC-MS/MS was achieved and validated. Chromatographic separation was conducted on an InertSustain® AQ-C18 column using 0.1% formic acid in water and acetonitrile as the mobile phase. Target compounds were extracted using acetonitrile/water (20:80, v/v). After the removal of lipids with acetonitrile-saturated hexane, the dissolved protein was denatured with acetic acid. A portion of the supernatant was passed through an Oasis® PRiME HLB cartridge to remove the matrix. This novel method was validated in accordance with the Japanese validation guidelines and exhibited good trueness, ranging from 86.3% to 96.2%, using matrix-matched calibration curves. The relative standard deviation of repeatability ranged from 1.0% to 6.3%, and that of within-laboratory reproducibility ranged from 1.6% to 7.1%. The limit of quantification was 1.0 µg kg-1 for all analytes. None of the 60 milk samples commercially available in Tokyo contained any analytes. This novel method exhibited high-quality performance and can easily be implemented for the routine monitoring of carbapenems, which are highly polar antibiotics in milk.

High-Fat Diet-Induced Diabetic Conditions Exacerbate Cognitive Impairment in a Mouse Model of Alzheimer's Disease Via a Specific Tau Phosphorylation Pattern

BACKGROUND

Epidemiological evidence has demonstrated a clear association between diabetes mellitus and increased risk of Alzheimer's disease (AD). Cerebral accumulation of phosphorylated tau aggregates, a cardinal neuropathological feature of AD, is associated with neurodegeneration and cognitive decline. Clinical and experimental studies indicate that diabetes mellitus affects the development of tau pathology; however, the underlying molecular mechanisms remain unknown.

OBJECTIVE

In the present study, we used a unique diabetic AD mouse model to investigate the changes in tau phosphorylation patterns occurring in the diabetic brain.

DESIGN

Tau-transgenic mice were fed a high-fat diet (n = 24) to model diabetes mellitus. These mice developed prominent obesity, severe insulin resistance, and mild hyperglycemia, which led to early-onset neurodegeneration and behavioral impairment associated with the accumulation of hyperphosphorylated tau aggregates.

RESULTS

Comprehensive phosphoproteomic analysis revealed a unique tau phosphorylation signature in the brains of mice with diabetic AD. Bioinformatic analysis of the phosphoproteomics data revealed putative tau-related kinases and cell signaling pathways involved in the interaction between diabetes mellitus and AD.

CONCLUSION

These findings offer potential novel targets that can be used to develop tau-based therapies and biomarkers for use in AD.

Enhanced mitochondrial oxidative metabolism in peripheral blood mononuclear cells is associated with fatty liver in obese young adults

Systemic inflammation underlies the association between obesity and nonalcoholic fatty liver disease (NAFLD). Here, we investigated functional changes in leukocytes' mitochondria in obese individuals and their associations with NAFLD. We analyzed 14 obese male Japanese university students whose body mass index was > 30 kg/m2 and 15 healthy age- and sex-matched lean university students as controls. We observed that the mitochondrial oxidative phosphorylation (OXPHOS) capacity with complex I + II-linked substrates in peripheral blood mononuclear cells (PBMCs), which was measured using a high-resolution respirometry, was significantly higher in the obese group versus the controls. The PBMCs' mitochondrial complex IV capacity was also higher in the obese subjects. All of the obese subjects had hepatic steatosis defined by a fatty liver index (FLI) score ≥ 60, and there was a positive correlation between their FLI scores and their PBMCs' mitochondrial OXPHOS capacity. The increased PBMCs' mitochondrial OXPHOS capacity was associated with insulin resistance, systemic inflammation, and higher serum levels of interleukin-6 in the entire series of subjects. Our results suggest that the mitochondrial respiratory capacity is increased in the PBMCs at the early stage of obesity, and the enhanced PBMCs' mitochondrial oxidative metabolism is associated with hepatic steatosis in obese young adults.

Effect of preoperative severity and location of lumbar intervertebral disc vacuum phenomenon on surgical outcomes after single-level transforaminal lumbar interbody fusion

OBJECTIVE

This study aimed to examine whether preoperative severity and location of lumbar intervertebral disc vacuum phenomenon (VP) influence surgical outcomes after single-level transforaminal lumbar interbody fusion (TLIF).

METHODS

We included 106 patients (age: 67.4 ± 10.4 years; 51 male/55 female) with lumbar degenerative diseases, who were treated with single-level TLIF. Severity of VP (SVP) score was measured preoperatively. SVP score at fused disc was used as SVP (FS) score, and at non-fused discs was used as SVP (non-FS) score. Surgical outcomes were assessed using Oswestry disability index (ODI) and visual analogue scale (VAS; low back pain (LBP), lower-extremity pain, numbness, LBP in motion, in standing, and in sitting). The patients were divided into Severe VP (FS or non-FS) and Mild VP (FS or non-FS) groups, and surgical outcomes were compared between the two groups. Correlations between each SVP score and surgical outcomes were analyzed.

RESULTS

There were no differences in surgical outcomes between the Severe VP (FS) and Mild VP (FS) groups. Postoperative ODI, VAS for LBP, lower-extremity pain, numbness, and LBP in standing were significantly worse in the Severe VP (non-FS) group than in the Mild VP (non-FS) group. SVP (non-FS) scores significantly correlated with postoperative ODI, VAS for LBP, lower extremity pain, numbness, and LBP in standing; however, SVP (FS) scores did not correlate with any surgical outcomes.

CONCLUSION

Preoperative severity of VP at fused disc is not associated with surgical outcomes, however, severity of VP at non-fused discs is correlated with clinical outcomes.

[Single-laboratory Validation Study and Surveillance Using an Improved Multiresidue Analytical Method for Veterinary Drugs in Livestock Products by LC-MS/MS]

A method for the rapid analysis of multiclass residual veterinary drugs in poultry muscle, egg, and raw milk was validated in accordance with Japanese guidelines. Using LC-MS/MS, 20 veterinary drugs, including sulfonamides, coccidiostats, and macrolides were analyzed in one injection. Analytes were extracted from the samples with acetonitrile and then dehydrated and salted out using magnesium sulfate, trisodium citrate, and sodium chloride. This method was assessed by performing recovery tests of chicken muscle, duck muscle, egg, and raw milk spiked with 20 new target analytes at concentrations of 10 and 100 µg/kg. According to this method, 17 out of 20 target analytes satisfied the guideline criteria in chicken muscle and duck muscle, and all 20 target analytes met the criteria in egg and raw milk. The limit of quantification was less than MRLs for all analytes. Residues were detected in 4 out of 99 samples and analyzed using the validated method, finding that the levels of all residues were lower than the limits of quantification. These results suggest that continuous monitoring for a new trend of veterinary drugs is necessary.

Postoperative change in lumbopelvic alignment after short-segment transforaminal lumbar interbody fusion is related to preoperative postural difference in lumbar lordosis

BACKGROUND

Postoperative changes in lumbar lordosis (LL) after transforaminal lumbar interbody fusion (TLIF) and the related factors are not well-understood. Recently, the preoperative difference in LL between standing and supine positions (DiLL) was proposed as a factor for predicting postoperative radiologic outcomes after short-segment TLIF. This study investigated the influence of DiLL on mid-term radiological outcomes after short-segment TLIF.

METHODS

Sixty-six patients with lumbar degenerative disease treated with short-segment TLIF (1-2 levels) who underwent lumbar spine standing radiographs at 3 months, 6 months, 1 year, 2 years, 3 years, 4 years, and 5 years postoperatively were divided into DiLL (+) and DiLL (-) groups (preoperative DiLL ≥0° and <0°, respectively). Associations between the postoperative change in LL and DiLL and clinical outcomes (Oswestry disability index (ODI) and Nakai score) were evaluated.

RESULTS

Temporary restoration of LL (+4.5°) until 1 year postoperatively and a subsequent decrease in LL from 1 to 5 years postoperatively (-5.3°) was observed in the DiLL (+) group. No postoperative change in LL was observed in the DiLL (-) group. Postoperative changes in LL were mainly observed in non-fused segments. The postoperative change in LL (ΔLL) until 1 year postoperatively had a significant positive association with DiLL (p = 0.00028), whereas ΔLL from 1 to 5 years postoperatively showed a significant negative association with DiLL (p = 0.010) and a positive association with Nakai score (p = 0.028). ΔLL until 5 years postoperatively showed a significant positive association with postoperative ODI improvement (p = 0.011).

CONCLUSIONS

DiLL (+) patients showed a specific time course with temporary LL restoration until 1 year postoperatively and a subsequent decrease in LL from 1 to 5 years postoperatively. Patients with larger postoperative increase in LL until 5 years postoperatively and lesser decrease in LL from 1 to 5 years postoperatively tended to show better mid-term clinical outcomes.

Aiming for dynamic behaviours of molecular metal chains

The dynamical functions of molecular metal chains, that could be derived from unique physical and chemical properties coupled with self-assembly of metal chain components, have largely been unexplored, and this review paper focuses on the dynamic behaviours of Pd chains supported by linear tetraphosphines, meso- and rac-Ph₂PCH₂P(Ph)CH₂P(Ph)CH₂PPh₂ recently reported, and the current development on fine-tuning of metal chains by introducing heterometal atoms, i.e. heterometallic molecular metal chains, that are considered as promising dynamical components in the next generation.

[Simultaneous Determination of Pesticide Residues in Brown Rice Using GC-MS/MS and LC-MS/MS]

This study developed a method that simultaneously detected 283 pesticide residues in brown rice using GC-MS/MS and LC-MS/MS. In this method, we examined the desirable amount of sodium chloride required for salting out and the SPE cartridge required for clean-up. Pesticide residues from the sample were extracted with acetonitrile using a homogenizer and mixed with salts including anhydrous magnesium, two types of citrate, and sodium chloride. The sample solution of the acetonitrile layer was cleaned up using the GCB/NH2 (200 mg/200 mg, 6 mL) SPE cartridge. The determination method was validated using two concentrations (0.01 and 0.1 μg/g) of 283 pesticides based on the validation guideline of the Ministry of Health, Labor and Welfare in Japan. Of the 283 pesticides, 250 were detected satisfactorily. In addition, 59 brown rice samples sold in Tokyo were surveyed using the same method. Out of 44 samples, 12 pesticide residues below MRLs were detected. Therefore, this developed method is useful for the simultaneous determination of pesticide residues in brown rice.

Comparison of pain and discomfort in supine and lateral positions after surgery for lumbar degenerative disease: A prospective randomized controlled study

INTRODUCTION

To compare postoperative pain and discomfort between supine and lateral positions after lumbar surgery, a prospective randomized controlled study was performed.

METHODS

Forty-three patients with lumbar degenerative disease, treated by decompression (n = 23) or fusion surgery (n = 20), were randomly assigned to be placed in either the supine (supine group: n = 21) or lateral (lateral group: n = 22) position postoperatively, and asked to maintain their position until a day after the surgery. Postoperative back pain and discomfort (visual analog scale [VAS], 0-100 mm) and the number of patients who could maintain their position were examined.

RESULTS

The VAS scores for back pain (supine: 64.9 ± 22.0, lateral: 55.7 ± 21.4) showed no significant difference between the positions. However, the supine group showed significantly more severe discomfort (75.6 ± 15.7) than the lateral group (64.9 ± 15.7, p = 0.039). Significantly fewer patients maintained their position in the supine group (28.2%) than in the lateral group (68.2%; p = 0.022). Among patients who underwent fusion surgery, significantly fewer patients maintained their position in the supine group (10.0%) than those in the lateral group (60.0%, p = 0.029).

CONCLUSION

Postoperative discomfort was significantly reduced in the lateral position than in the supine position; thus, the lateral position is more suitable after lumbar surgery in terms of postoperative discomfort.

Electrophysiological characteristics and catheter ablation of atypical fast-slow atrioventricular nodal reentrant tachycardia using an inferolateral left atrial slow pathway

Background

Understandings of subtypes of atypical atrioventricular nodal reentrant tachycardia (AVNRT) using variants of slow pathway (SP) are still growing. Inferolateral (inf-lat-) left atrial (LA) SP is a rare variant extending into an inf-lat-LA along the mitral annulus (MA).

Purpose

To characterize an unknown subtype of atypical fast-slow (F/S-) AVNRT using an inf-lat-LA-SP as a retrograde limb (inf-lat-LA-F/S-AVNRT).

Methods

This Japanese multicenter retrospective study enrolled 4 patients of inf-lat-LA-F/S-AVNRT that was characterized by the earliest site of atrial activation during tachycardia (EAA) between 3 and 6 o'clock along the MA. The diagnosis was made by an exclusion of AV reentrant tachycardia (AVRT) and atrial tachycardia (AT) according to the standard criteria and was confirmed by successful elimination of tachycardia and the inf-lat-LA-SP.

Results

Surface ECG during tachycardia revealed long RP appearance except one who had short RP due to a short conduction time across the inf-lat-LA-SP. During tachycardia, far-field LA activation preceding near-field activation of coronary sinus (CS) musculature was visible in the CS recording in 2. Retrograde conduction via the inf-lat-LA-SP with a decremental delay was consistently reproducible with ventricular stimulation in 2, 1 of whom had double atrial response, while it was always masked by the presence of a retrograde conduction via the fast pathway in 1 and a retrograde block at the lower common pathway in 1. An injection of a small dose of ATP transiently interrupted a retrograde conduction over the inf-lat-LA-SP, suggesting its ATP-sensitivity. Exclusion of AVRT was made by no resetting of tachycardia with left ventricular extrastimulus in 2 and VA dissociation during overdrive pacing of tachycardia in remaining 2. Exclusion of AT was made by V-A-V response after ventricular entrainment in 1 and termination without atrial capture by ventricular pacing in 2. Ablation of the right-sided SP was unsuccessful to eliminate the tachycardia, but ablation at or near the EAA by transseptal approach was successful to cure the tachycardia, associated with an elimination of a retrograde conduction over the inf-lat-LA-SP following a development of an accelerated junction rhythm in all. Low-frequency potentials preceding local atrial activation, consistent with a retrograde activation via the inf-lat-LA-SP were detected along the MA medial to the EAA in 1.

Conclusions

Differential diagnosis of tachycardia with the EAA in the inf-lat-LA and especially long RP appearance should include inf-lat-LA-F/S-AVNRT. Presumed arrhythmogenic substrate of the inf-lat-LA-SP seemed to be consistent with the remnant of embryogenic AV ring tissue in the electropharmacological and locational characteristics. Successful elimination of this AVNRT can be obtained by ablation of the inf-lat-LA-SP, but not of the right-sided SP.

Funding Acknowledgement

Type of funding sources: None.

The expression and phosphorylation of SMAD3 protein in microglia and astrocytes of the rat hippocampus after transient global cerebral ischemia

SMAD3 protein transduces signals from TGF-β and activins. In vitro studies have shown that SMAD3 plays an important role in regulating of micoglia and astrocytic function. However, there is little information on the association between SMAD3 signaling and the pathophysiology of the glial cells in the post-ischemic hippocampus. In this study, we examined the time-course changes in the expression and phosphorylation of SMAD3 in the rat hippocampus using a rat model of global cerebral ischemia. Most pyramidal neuronal cells in the CA1 region died within 7 days after ischemia. The number of SMAD3- or phosphorylated SMAD3 (p-SMAD3)-immunopositive microglia or astrocytes increased in the CA1 region 7 days after ischemia. Real-time PCR analysis showed an increase in the level of TGF-β1 mRNA in the hippocampus after ischemia. Intracerebroventricular injection of SB525334, a selective inhibitor of TGF-β receptor I kinase (ALK5), reduced the ischemia-induced p-SMAD3 immunoreactivity in the microglia and astrocytes. By contrast, intracerebroventricular injection of SB525334 did not affect the ischemia-induced neuronal cell death. These results suggest that ischemia-induced SMAD3 phosphorylation in the microglia and astrocytes of post-ischemic hippocampi is associated with tissue repair and not neuroprotection.

Empagliflozin improves cardiac mitochondrial function and survival through energy regulation in a murine model of heart failure

BACKGROUND

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been demonstrated to have beneficial effects on HF in large clinical trials; however, the mechanisms remain to be elucidated. The aim of this study was to clarify the mechanisms by which empagliflozin, one of SGLT2 inhibitors, affects heart failure.

METHOD AND RESULTS

Eight-week-old male mice deficient for heart and skeletal muscle-specific manganese superoxide dismutase (MnSOD-cKO mice), a murine model of dilated cardiomyopathy, were given food mixed with or without 10 mg/kg empagliflozin for 7 weeks and evaluated. Both the survival rate and cardiac fibrosis were significantly improved in the empagliflozin group. The capacity for oxidative phosphorylation in cardiac mitochondria was significantly upregulated as measured with Oxygraph-2k respirometer, and blood lactate levels produced by anaerobic metabolism were significantly lower in the empagliflozin group. Energy expenditure was significantly improved in the empagliflozin group, measured by respiratory gas analysis, with a concomitant reduction in serum leptin concentration and increase in food intake. A moderate amount of glucose was excreted in urine in the empagliflozin group; however, the available energy substrate in the body nonetheless expanded because of the much higher caloric intake.

CONCLUSIONS

We conclude that empagliflozin improved cardiac mitochondrial function and upregulated energy metabolism even in HF in mice. These findings provide novel mechanisms for the beneficial effects of SGLT2 inhibitors on HF.

Unexpectedly rapid decrease in the size of a spinal epidural abscess after percutaneous posterior pedicle screw fixation without decompression surgery: a case report

INTRODUCTION

Spondylodiscitis accompanying spinal epidural abscess is often treated with decompression surgery when there are neurological symptoms. We report a case of spondylodiscitis accompanying spinal epidural abscess with severe lower extremity pain that was successfully treated with percutaneous posterior pedicle screw fixation without decompression surgery.

CASE PRESENTATION

A 53-year-old man was admitted to our hospital with severe low back pain (LBP), lower extremity pain and numbness, and fever. Lumbar magnetic resonance imaging (MRI) revealed spondylodiscitis at L2-L3 and a small epidural abscess located ventrally in the spinal canal. Initially, the patient was treated conservatively with empirical antibiotics. However, the lower extremity symptoms worsened and the epidural abscess expanded cranially to the T12 level. Percutaneous pedicle screw fixation without decompression was performed thirty-three days after admission. Postoperatively, the LBP and lower extremity pain dramatically improved. A postoperative MRI performed one week post-operatively showed an unexpectedly rapid decrease in the size of the epidural abscess, although no decompression surgery was performed. Two months after surgery, the epidural abscess completely disappeared. At the final follow-up (five years postoperatively), no recurrence of epidural abscess was observed, and the patient had no symptoms or disturbance of activities of daily living.

DISCUSSION

This surgical strategy should be carefully selected for patients with spondylodiscitis with accompanying spinal epidural abscess who have lower extremity symptoms. The stabilising effect of pedicle screw fixation may be advantageous for controlling spinal infections. Percutaneous posterior pedicle screw fixation without decompression is an optional treatment for spondylodiscitis accompanying spinal epidural abscess.

Prediction of anatomically and biomechanically feasible precision grip posture of the human hand based on minimization of muscle effort

We developed a method to estimate a biomechanically feasible precision grip posture of the human hand for a given object based on a minimization of the muscle effort. The hand musculoskeletal model was constructed as a chain of 21 rigid links with 37 intrinsic and extrinsic muscles. To grasp an object, the static force and moment equilibrium condition of the object, force balance between the muscle and fingertip forces, and static frictional conditions must be satisfied. We calculated the hand posture, fingertip forces, and muscle activation signals for a given object to minimize the square sum of the muscle activations while satisfying the above kinetic constraints using an evolutionary optimization technique. To evaluate the estimated hand posture and fingertip forces, a wireless fingertip force-sensing device with two six-axis load cells was developed. When grasping the object, the fingertip forces and hand posture were experimentally measured to compare with the corresponding estimated values. The estimated hand postures and fingertip forces were in reasonable agreement to the corresponding measured data, indicating that the proposed hand posture estimation method based on the minimization of muscle effort is effective for the virtual ergonomic assessment of a handheld product.

Cooccurrence of Fragility Fracture of the Pelvis with Lumbar Degenerative Disease: A Case Report

Introduction

Fragility fractures of the pelvis (FFP) are caused by low-energy impacts and can occur spontaneously in patients with severe osteoporosis. The clinical symptoms of FFP are frequently vague and nonspecific. Moreover, the symptoms of FFP can mimic lumbar spine pathologies. Therefore, accurate diagnosis of FFP is often difficult and the fracture may be misdiagnosed as lumbar degenerative disease. However, little is known regarding what kind of symptoms due to lumbar degenerative disease are similar to the symptoms of FFP.

Case Report

We encountered two cases in which FFP developed during the treatment of lumbar degenerative disease with radiculopathy. Both patients had undergone conservative treatment for lumbar degenerative disease, but their symptoms gradually worsened and they presented with gait disturbance. FFP was diagnosed by imaging, and surgery was required in one case. Both cases showed L3 foraminal stenosis on the image, and the symptoms of L3 radiculopathy presented with thigh pain, hip pain, and knee pain, which is similar to the pain site of FFP. Therefore, diagnosis of FFP was difficult.

Conclusion

In lumbar degenerative diseases presenting with radiculopathy, the pain site may be similar to that of FFP, which may make diagnosis of FFP difficult. Therefore, especially in patients with lumbar degenerative disease presenting with L3 radiculopathy, it is necessary to consider the possibility of FFP and perform MRI imaging to make an early diagnosis when the symptoms change.

Postoperative loss of correction after combined posterior and anterior spinal fusion surgeries in a lumbar burst fracture patient with Class II obesity

Background:

When treating thoracolumbar fractures with severe cranial endplate injury but no or slight caudal endplate injury, it is debatable whether anterior fusion should be performed only for the injured cranial level, or for both cranial and caudal levels. We report an unexpected postoperative correction loss after combined multilevel posterior and single-level anterior fusion surgery in a patient with obesity.

Case Description:

A 28-year-old male with Class II obesity was brought to the emergency room with an L1 burst fracture with spinal canal involvement. Cranial endplate injury was severe, whereas caudal endplate injury was mild. The first surgery with 1-above 1-below posterior fixation failed to achieve sufficient stability; thus, additional surgeries (3-above 3-below posterior fixation and single-level T12-L1 anterior fusion) were performed. Postoperatively, the local kyphosis angle (LKA) between T12 and L2 was 22° in the lateral lying position and 29° in the standing position. Twenty-one-month post surgery, bony fusion between T12 and L1 was observed, and the LKA was 28° in both the lateral lying and standing positions. After posterior implants were removed 24 months after the surgery, significant correction loss both at the T12-L1 segment (6°) and L1-L2 segment (6°) occurred, and LKA was 40° at the final follow-up.

Conclusion:

In this patient, an intense axial load due to excessive body weight was at least one of the causes of postoperative correction loss. Postural differences in LKA may be useful to evaluate the stability of thoracolumbar fractures after fusion surgery and to predict postoperative correction loss.

[Surveillance of Acaricides in Honey]

By using the LC-MS/MS method developed by us, we determined the residual amounts of acaricides in honey samples commercially available in Tokyo from April 2015 to March 2021. The results of analyzing 127 honey samples, amitraz was detected in 85 samples at the level of 1.1-34.1 μg/kg. Propargite was detected in 3 samples at 2.4-3.8 μg/kg. None of them was beyond the Japanese MRLs or uniform limits. In these survey for 6 years, amitraz was detected in high rate throughout the year. But, the present results imply that amitraz has been used properly in actual bee-keeping because of no violation of MRL and less fluctuation in the detected levels. On the other hand, propargite was detected at the levels over LOQ in domestic honey samples for the first time in 2020, which may suggest a new trend of acaricide use in apiculture in Japan.

VULCANIZATION FOR REINFORCEMENT OF RUBBER

Sulfur cross-linking reagents play critical roles not only in cross-linking rubber chains but also in controlling network morphology for reinforcement of rubber. Zinc oxide (ZnO) is clearly discovered as the main component for both roles. Especially, the importance of network inhomogeneity, which is significantly governed by the dispersion of ZnO particles, is emphasized for reinforcing rubber materials. Specifically, the formation of network domains and their continuous structures is discussed by combining the mechanical properties of the vulcanizates from the viewpoint of the reinforcement effect of rubber. Two continuous structures of network domains are termed as the network-domain cluster and network-domain network, which are observed by atomic force microscopy. The ZnO particles play a role as template for the formation of the continuous structures of network domains. The findings provide us with a practical hint for producing high-performance rubber materials.

Minimally Invasive "Crab-Shaped Fixation" for Treating Patients with Fragility Fractures of the Pelvis

Introduction

In the aging society, fragility fracture of the pelvis (FFP) has become a problem. Although strong and minimally invasive fixation is required in FFP surgery, reports on relevant surgical results are scarce. Crab-shaped fixation (CSF) is a spinopelvic fixation that involves reconstruction of the posterior pelvic ring using spinal instrumentation. This study aimed to evaluate the walking ability and perioperative complications of patients who underwent CSF for FFP.

Methods

We included patients diagnosed with unstable FFPs, including sacral fracture, who required hospitalization. Demographic data, such as age, sex, bone mineral density, and Rommens classification, were evaluated. Surgical findings included estimated blood loss, operation time, and perioperative complications. The improvement in postoperative walking ability was evaluated based on the length of the postoperative period before the initiation of walker training and whether walking aids were required at 6 months post-surgery, compared with those who received conservative treatment for FFP.

Results

Our study included 6 cases that received CSF and 16 cases that received conservative treatment, in which all were females and presented with sacral fractures. The average age of the surgical patients, the operation time, and the estimated blood loss were 79.5±14.7 years, 180.7±28.7 min, and 124.2±29.4 mL, respectively. The average length of the postoperative period prior to the initiation of walker training was 10.8±12.3 days, which was significantly shorter than that of conservative treatment. With regard to perioperative complications, poor reduction of fracture dislocation was observed in one case as well as surgical site infection in another case, but the walking ability improved in all cases.

Conclusions

We evaluated the results of the posterior pelvic ring reconstruction with CSF for patients with vertically unstable FFPs, including sacral fractures. CSF is minimally invasive and would be useful as it allowed walker training during the early postoperative period, which improved patients' walking ability even during the in situ pelvic ring reconstruction.

Predictors of Spontaneous Restoration of Lumbar Lordosis after Single-Level Transforaminal Lumbar Interbody Fusion for Degenerative Lumbar Diseases

Introduction

Preoperative factors that predict postoperative restoration of lumbar lordosis (LL) are not well understood. To investigate whether preoperative postural correction of LL, sagittal malalignment, or lumbar flexibility are associated with the postoperative restoration of LL in patients treated with a single-level transforaminal lumbar interbody fusion (TLIF), a retrospective cohort study was conducted.

Methods

We enrolled 104 patients (mean age: 67.5±10.7 years old; 47 men and 57 women) with lumbar degenerative diseases treated with a single-level TLIF. The pre- and postoperative LL were examined using lateral radiographs in the standing position and computed tomography (CT) images in the supine position. The correlation between postoperative LL restoration and preoperative postural correction of LL (difference in LL between the standing and supine positions: D-LL), sagittal imbalance (pelvic incidence minus LL: PI-LL), and lumbar flexibility (difference in LL between the flexion and extension postures) were analyzed. Patients were divided into two groups according to the D-LL (D-LL≥0° and D-LL<0°). The rates of postoperative LL restoration (postoperative LL-preoperative LL in standing) were compared between the two groups.

Results

Multiple regression analysis performed after adjustment for age, gender, body mass index, and cage angle revealed that postoperative LL restoration was significantly correlated with D-LL (p<0.001), but not with PI-LL, and lumbar flexibility. Patients with a preoperative D-LL≥0° showed a significantly greater increase of LL after TLIF (7.1°±11.2°) than those with D-LL<0° (1.4°±6.6°) (p=0.003).

Conclusions

A preoperative evaluation of a lateral radiograph or CT taken in the supine position is useful in predicting postoperative improvement of sagittal alignment. Postoperative improvement of sagittal spinopelvic alignment would be expected when LL is corrected in the supine position preoperatively. Surgeons should pay attention to the postural correction of LL when performing short-segment fusion surgery for lumbar degenerative disease with sagittal malalignment.

Unsymmetric Dinuclear RhI2 and RhIRhIII Complexes Supported by Tetraphosphine Ligands and Their Reactivity of Oxidative Protonation and Reductive Dechlorination

Two linear tetradentate phosphine ligands, meso-Ph₂PCH₂P(Ph)CH₂XCH₂P(Ph)CH₂PPh₂ (X = CH₂ (meso-dpmppp), NBn (meso-dpmppmNBn; Bn = benzyl)) were utilized to synthesize unsymmetrical dinuclear Rh^I complexes, [Rh₂Cl₂(meso-dpmppp)(L)] (L = XylNC (1a), CO (1b)) and [Rh₂Cl₂(meso-dpmppmNBn)(L)] (L = XylNC (1c), CO (1d)), where electron-deficient Rh^I → Rh^I centers with 30 valence electrons are supported by a tetraphosphine in an unusual cis-/trans-P,P coordination mode. The Rh^I dimers of 1a-d were treated with HCl under air to afford the Rh^I → Rh^III dimers with 32 e^-, [Rh₂Cl₄(meso-dpmppp)(L)] (L = XylNC (4a), CO (4b)) and [Rh₂Cl₄(meso-dpmppmNBn)(L)] (L = XylNC (4c), CO (4d)), via intermediate hydride complexes, [{RhCl₂(μ-H)RhCl(L)}(meso-dpmppp)] (L = XylNC (2a), CO (2b)) and [{RhCl₂(μ-H)RhCl(L)}(meso-dpmppmNBn)] (L = XylNC (2c), CO (2d)), and [{Rh(H)Cl₂(μ-Cl)Rh(L)}(meso-dpmppp)] (L = XylNC (3a), CO (3b)) and [{Rh(H)Cl₂(μ-Cl)Rh(L)}(meso-dpmppmNBn)] (L = XylNC (3c), CO (3d)). The hydride intermediates 2 and 3 were monitored under nitrogen by ¹H{³¹P} and ³¹P{¹H} NMR techniques to reveal two reaction pathways depending on the terminal auxiliary ligand L. Further, the reductive dechlorination converting Rh^IRh^III (4b,d) to Rh^I₂ (1b,d) was accomplished with a CO terminal ligand by reacting with various amines that acted as one-electron reducing agents through an inner-sphere electron transfer mechanism. DFT calculations were performed to elucidate the electronic structures of 1a-d and 4a-d and to estimate the structures of the hydride intermediate complexes 2 and 3.

Chiral Dinuclear Eu(III), Tb(III), and Y(III) Complexes Supported by P-Stereogenic Linear Tetraphosphine Tetraoxide

A P -stereogenic linear tetraphosphine tetraoxide, ( R,R )- or ( S,S )-dpmppm(=O) 4 , was synthesized to prepare C 2 dinuclear M(hfa) 3 complexes (M = Eu, Tb, Y) as the first example of lanthanide(III) complexes with P -chiral multidentate phosphine oxides. The mononuclear M(hfa) 3 complexes (M = Eu, Y) with a P -chiral diphosphine oxide, tpdpb(=O) 2 , were also prepared, and comparison of their photophysical properties for the Eu(III) complexes revealed that significant chiral induction from the P -chiral centers arises on the achiral M(hfa) 3 units through intramolecular π-π stacking constraint in the dinuclear system.

Mechanical testing of cephalomedullary nail lag screws after the addition of hydroxyapatite substitutes

OBJECTIVE

To compare the effects of 3 implant designs, with and without hydroxyapatite reinforcement, on push/pull-out strength and rotational torque.

METHODS

Three implant designs (Gamma 3, INTERTAN, and PFNA-II) were selected for comparison. A hydroxyapatite cylinder (NEOBRACE) was used to reinforce the interface between the femoral head and the lag screw. Maximum push-out strength, maximum pull-out strength, and peak rotational torque were measured in cellular blocks mimicking osteoporotic cancellous bone, with and without NEOBRACE.

RESULTS

In the push-out test, INTERTAN produced a significantly higher push-out strength in osteoporotic bone density cellular blocks than the other lag screws and blades (P < .05). With the addition of NEOBRACE, push-out strength was significantly higher for INTERTAN and PFNA-II (P < .05) than for the non-NEOBRACE group. In the pull-out test, INTERTAN produced a significantly higher pull-out strength in the osteoporotic bone density cellular blocks than did the other lag screws and blades (P < .05). With the addition of NEOBRACE, the pull-out strengths of INTERTAN and Gamma 3 versus those of the non-NEOBRACE group significantly increased (P < .05). In the rotational torque test, INTERTAN produced significantly greater rotational torque in the osteoporotic cellular blocks than the other lag screws and blades (P < .05). The addition of NEOBRACE resulted in a significant increase in rotational torque only for INTERTAN (P < .05).

CONCLUSION

The use of NEOBRACE supported an increase in push/pull-out strength and rotational torque, especially in systems with a relatively increased bone or implant interface area.Level of Evidence: Level V.

The Quantity and Quality of Lumbar Muscles and Lumbopelvic Parameters in Patients With Degenerative Spondylolisthesis

Introduction

Lumbar degenerative spondylolisthesis (DS) is one of the most common causes of low back pain. The lumbar muscles, such as the psoas major (PM), erector spinae (ES), and multifidus (MF) muscles, play an important role in the stability and functional movement of the lumbar spine. The quantities and qualities of these muscles may be related to the occurrence of DS and lumbopelvic parameters, such as lumbar lordosis (LL) and sacral slope (SS). However,the influence of lumbar muscles on DS and lumbopelvic alignment is not well understood.

Methods

Patients with L4 DS (DS group, n=25) and without DS (non-DS group, n=25) were included. Using sagittal reconstructed CT images of patients who visited our hospital for reasons other than low back disorders, LL, upper lumbar lordosis ([ULL] L1-L4), lower lumbar lordosis ([LLL] L4-S1), and SS were examined. To evaluate the quantity and quality of lumbar muscles, the gross cross-sectional area (GCSA), functional cross-sectional area (FCSA), and fat infiltration (FI) of the PM, ES, and MF muscles were measured by CT images. The lumbopelvic parameters, FCSA, GCSA, and FI of lumbar muscles were compared between the two groups. Then, each lumbar muscle parameter was analyzed for correlation with DS and lumbopelvic parameters.

Results

DS patients displayed significantly greater ULL and lower FI of the PM and ES muscles than non-DS patients (p=0.0078, 0.031, and 0.010, respectively). The FI of the ES muscle was significantly correlated with the presence of DS (p=0.010). The FCSA of the ES and MF muscles and the GCSA of the MF muscle showed a significant correlation with LL and SS in the non-DS group (p<0.05), but not in the DS group..

Conclusion

ULL was greater in L4 DS patients, possibly related to the better quality of the ES muscle. All DS patients showed mild (grade I) spondylolisthesis, suggesting the possibility that lumbar muscle quality is better in patients with mild DS than in those without DS. The ES and MF muscles may play an important role in maintaining the lumbar lordotic angle in non-DS patients but not in DS patients.

Effects of the difference between lumbar lordosis in the supine and standing positions on the clinical outcomes of decompression surgery for lumbar spinal stenosis

OBJECTIVE

The authors sought to evaluate the relationship between the difference in lumbar lordosis (DiLL) in the preoperative supine and standing positions and spinal sagittal alignment in patients with lumbar spinal stenosis (LSS) and to determine whether this difference affects the clinical outcome of laminectomy.

METHODS

Sixty patients who underwent single-level unilateral laminectomy for bilateral decompression of LSS were evaluated. Spinopelvic parameters in the supine and standing positions were measured preoperatively and at 3 months and 2 years postoperatively. DiLL between the supine and standing positions was determined as follows: DiLL = supine LL - standing LL. On the basis of this determination patients were then categorized into DiLL(+) and DiLL(-) groups. The relationship between DiLL and preoperative spinopelvic parameters was evaluated using Pearson's correlation coefficient. In addition, clinical outcomes such as visual analog scale (VAS) and Oswestry Disability Index (ODI) scores between the two groups were measured, and their relationship to DiLL was evaluated using two-group comparison and multivariate analysis.

RESULTS

There were 31 patients in the DiLL(+) group and 29 in the DiLL(-) group. DiLL was not associated with supine LL but was strongly correlated with standing LL and pelvic incidence (PI) - LL (PI - LL). In the preoperative spinopelvic alignment, LL and SS in the standing position were significantly smaller in the DiLL(+) group than in the DiLL(-) group, and PI - LL was significantly higher in the DiLL(+) group than in the DiLL(-) group. There was no difference in the clinical outcomes 3 months postoperatively, but low-back pain, especially in the sitting position, was significantly higher in the DiLL(+) group 2 years postoperatively. DiLL was associated with low-back pain in the sitting position, which was likely to persist in the DiLL(+) group postoperatively.

CONCLUSIONS

We evaluated the relationship between DiLL and spinal sagittal alignment and the influence of DiLL on postoperative outcomes in patients with LSS. DiLL was strongly correlated with PI - LL, and in the DiLL(+) group, postoperative low-back pain relapsed. DiLL can be useful as a new spinal alignment evaluation method that supports the conventional spinal sagittal alignment evaluation.

Electrochemical hydrogen formation catalysed by a Pd8 string

The linear Pd₈ complex supported by tetraphosphines reacted with HBF₄ to give an unprecedented linear tetrapalladium complex with a terminal hydride, which promoted electrocatalytic hydrogen formation from HBF₄ in acetonitrile. The 1D coordination polymer of Pd₈ chain confined within Nafion film was applied to the electrocatalytic H₂ formation.

Fast-slow atrioventricular nodal reentrant tachycardia phenotype mimicking the slow-slow type

Background

Fast-slow (F/S-) atrioventricular (AV) nodal reentrant tachycardia (AVNRT) is characterized by a short atrio-His (AH) interval and the earliest site of atrial activation (EAA) in the proximal coronary sinus (EAA-CS), while slow-slow (S/S-) AVNRT presents a long AH interval and EAA-CS. Those intracardiac appearances are initial indicators for making a diagnosis.

Purpose

To identify an unknown phenotype of F/S-AVNRT.

Methods

Among 46 consecutive patients with F/S-AVNRT, 6 patients (1 man, age 59±9) had an apparent but not typical (pseudo-) S/S-AVNRT during an electrophysiologic study. In 2 patients, pseudo-S/S-AVNRT was clinically documented.

Results

In all 6 patients, the diagnosis of F/S-AVNRT was made by an exclusion of atrial tachycardia with findings of 1) a V-A-V response following ventricular entrainment or 2) termination without atrial capture by ventricular pacing, and an exclusion of AV reentrant tachycardia with a ventriculoatrial dissociation during an initial (so-called QRS transition) zone of ventricular entrainment. An initial A-A-V activation sequence on atrial induction of F/S-AVNRT observed in 1 patient and Wenckebach-type AV block during ongoing F/S-AVNRT developing in 3 patients suggested the presence of the lower common pathway (LCP). Like the typical S/S-AVNRT, pseudo-S/S-AVNRT was induced with atrial stimulation after a jump in the AH interval or double ventricular response. However, in all patients, the pseudo-S/S-AVNRT transited to F/S-AVNRT following AV block in a single cycle and/or pseudo-S/S-AVNRT transited from spontaneously or triggered by atrial contractions. Importantly, on these transitions, the atrial cycle length (CL) and EAA-CS remained unchanged, that is, the atrial CL of S/S-AVNRT was almost identical to that of F/S-AVNRT, suggesting that the essential circuit of both tachycardias was identical. Actually, both tachycardias were cured by ablation at a single site in the traditional slow pathway (SP). Collectively, the pseudo-S/S-AVNRT was diagnosed as another phenotype of F/S-AVNRT accompanied by sustained antegrade conduction via another bystander (likely the left-sided or superior) SP breaking through the His bundle owing to the repetitive antegrade block at the LCP occurring by linking phenomenon, thus representing a long AH interval during the ongoing F/S-AVNRT. When the antegrade conduction is blocked at the bystander SP during the pseudo-S/S-AVNRT, releasing the linking phenomenon, the subsequent antegrade conduction reach the His-bundle via the fast pathway, thus returning to F/S-AVNRT.

Conclusions

An unknown, but not rare F/S-AVNRT phenotype exists that apparently mimics the typical S/S-AVNRT and is also an unknown subtype of apparent S/S-AVNRT. The presence of this pseudo-S/S-AVNRT suggests the limitation of classifying types of AVNRT based on AH and HA intervals during tachycardia. Understandings of this phenotype can advance a diagnosis of atypical AVNRT with multiple phenotypes.

Funding Acknowledgement

Type of funding sources: None.

Association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan: a cohort study

Background

There is an ongoing controversy regarding the necessity of single-photon emission computed tomography (SPECT) for patients with ischemic heart diseases after the publication of the results of the ISCHEMIA trial.

Purpose

We aimed to evaluate the association of the extent of myocardial ischemia with outcomes in patients with suspected coronary artery disease in Japan.

Methods

From the data of 2780 patients with stable angina who were enrolled prospectively between January 2006 and March 2008 in Japan and had undergone physician-referred non-invasive imaging tests, 1205 patients managed with SPECT were stratified by 10% myocardial ischemia. Major adverse cardiac events (MACEs), including death, myocardial infarction, hospitalization for heart failure, and late revascularization, were followed-up for 1 year.

Results

Patients with ≥10% myocardial ischemia (n=173) were older than patients with &lt;10% myocardial ischemia (n=1032) and had a significantly higher 1-year cumulative incidence of MACEs (9.1% vs. 1.2%, P&lt;0.0001). After adjusting for confounders, the risk of ≥10% myocardial ischemia relative to &lt;10% myocardial ischemia for MACEs remained significant (adjusted hazard ratio [95% confidence interval], 2.40 [1.09–5.26], P=0.029).

Conclusion

The presence of ≥10% myocardial ischemia was significantly associated with the 1-year risk for MACEs in Japanese patients with suspected coronary artery disease.

Funding Acknowledgement

Type of funding sources: None. Study flowchartOutcomes

Empagliflozin improves prognosis and energetic properties through modulating mitochondrial function in failing murine hearts

Background/Introduction

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have been reported to have beneficial effects on heart failure in large clinical trials; however, the underlying mechanism is still unclear.

Purpose

The purpose of this study is to elucidate the mechanism of cardioprotective effect of empagliflozin in heart failure.

Methods

Eight-week-old mice deficient in cardiac and skeletal muscle-specific manganese superoxide dismutase, a mouse model of dilated cardiomyopathy (MnSOD-cKO mice), were given food mixed with or without 10 mg/kg empagliflozin for seven weeks and evaluated. Mitochondrial function in the cardiac muscle were measured by a high-resolution respirometer, Oxygraph-2K. Respiratory gas analysis were performed by indirect calorimetry (ARCO 2000) to estimate the energy consumption and energetic substrates.

Results

The survival rate (P=0.015) and cardiac fibrosis (P=0.036) were significantly improved in the empagliflozin group. The capacity of oxidative phosphorylation in cardiac mitochondria was significantly improved by empagliflozin. Blood lactate levels were decreased in the empagliflozin group, indicating that energy such as ATP could be produced without resorting to anaerobic metabolism.

Respiratory gas analysis revealed significant improvement in energy expenditure along with increase in food intake. Respiratory quotient was not different between the two groups, showing the consumption of the carbohydrate to fat rate was not changed by empagliflozin in this study. Ketone levels in blood and HbA1c were neither significantly different between the two groups. Although a moderate amount glucose was excreted in urine in the empagliflozin group (128.3±20.4 mg/day, 0.51±0.08 kcal/day), the available energy substrates in the whole body nonetheless expanded because of the increased caloric intake (10.58±0.72 in control group vs. 13.55±0.08 kcal/day in empagliflozin group, P=0.018).

Conclusion(s)

We have shown that empagliflozin improved myocardial mitochondrial function and increased energy metabolism, which was accompanied by adequate energy intake and uptake, even in heart failure. Empagliflozin decreased myocardial fibrosis and improved prognosis in failing murine hearts through positive energetical properties including mitochondrial function. The finding that empagliflozin modulates cardiac metabolism in a positive way provides a novel mechanism for the cardioprotective effect of SGLT2 inhibitors in heart failure.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): Boehringer Ingelheim Empa improved prognosis in HFEmpa improved mitochondrial function

Octapalladium Strings Trap C60 and C70 Fullerenes Affording Metal-Chain-Wired Bucky Balls

Reactions of Pd₈ strings supported by meso-Ph₂ PCH₂ P(Ph)CH₂ P(Ph)CH₂ PPh₂ (meso-dpmppm) ligands, [Pd₈ (meso-dpmppm)₄ (L)₂ ]⁴⁺ (L=CH₃ CN (1), XylNC (2)) with C₆₀ resulted in the exclusive formation of unprecedented metal-chain-wired C₆₀ bucky balls, [{Pd₄ (meso-dpmppm)₂ (L)}₂ (C₆₀ )]⁴⁺ (L=CH₃ CN (11), XylNC (12)), in which a C₆₀ fullerene is trapped in the central Pd-Pd junction, as unambiguously established by spectroscopic, X-ray crystallographic, and theoretical techniques. The similar reaction of Pd₈ strings supported by rac-dpmppm, [Pd₈ (rac-dpmppm)₄ (CH₃ CN)₂ ]⁴⁺ (3) also afforded a racemic mixture of [{Pd₄ ((R*,R*)-dpmppm)₂ (CH₃ CN)}₂ (C₆₀ )]⁴⁺ (13) without scrambling the Pd₄ fragments with (R,R)- and (S,S)-dpmppm ligands. Consequently, those of enantiopure chiral Pd₈ strings, [Pd₈ ((R*,R*)-dpmppm)₄ (CH₃ CN)₂ ]⁴⁺ , certainly afforded chiral bucky balls of [{Pd₄ ((R*,R*)-dpmppm)₂ (CH₃ CN)}₂ (C₆₀ )]⁴⁺ (13_RR and 13_SS ), that exhibit mirror-image circular dichroism spectra. The reactions of 1 and 2 were also applied for trapping a C₇₀ fullerene to give 2 : 1 adducts of [{Pd₄ (meso-dpmppm)₂ (L)}₂ (C₇₀ )]⁴⁺ (L=CH₃ CN (21), XylNC (22)). These results provide useful information for creating a platform to develop dimensionally and chirality controlled metal-carbon nanocomposite materials.

Computed Tomographic Assessment of Age- and Gender-Specific Sagittal Lumbopelvic Alignment in a Japanese Population

Introduction

Previous studies have reported differences in lumbopelvic alignment between standing and supine positions. Computed tomography (CT) images taken in the supine position are often used for clinical studies in addition to standing radiographs, although not frequently. Our study aims to clarify normative values of CT-evaluated lumbopelvic parameters and the characteristics of age- and gender-related lumbopelvic alignment in the supine position.

Methods

Patients undergoing CT scans of abdominal or lumbar regions for reasons other than low back disorders were included (n=581). Sagittal multiplanar reconstruction CT images were obtained, and lumbar lordosis (LL), L5-S1 angle, and sacral slope (SS) were measured. Mean values of the parameters in patients aged 59 years and under, 60-69, 70-79, and 80 and over, and in males and females, were calculated. Age- and gender-related differences in these parameters were statistically analyzed.

Results

Among the four age groups, patients 80 years and over showed significantly lower LL and SS than patients aged 70-79. Females 80 years and over showed significantly lower LL and SS than all other age groups, but those in males did not. The comparison between males and females showed no significant differences in LL and SS; however, the L5-S1 angle was significantly higher in males than in females. In patients 80 years and over, females showed significantly lower LL and SS than in males.

Conclusions

This study provides normative CT-evaluated lumbopelvic parameters, such as LL, L5-S1 angle, and SS, which will be utilized for comparisons in future studies. The present study first revealed that pelvic retroversion and lumbar kyphosis occur in elderly females in the supine position, which raised a possibility that age-related decrease of LL and SS in females occurs at an older age in the supine position than in the standing position.

Preparation and Readout of Multielectron High-Spin States in a Gate-Defined GaAs/AlGaAs Quantum Dot

We report the preparation and readout of multielectron high-spin states, a three-electron quartet, and a four-electron quintet, in a gate-defined GaAs/AlGaAs single quantum dot using spin filtering by quantum Hall edge states coupled to the dot. The readout scheme consists of mapping from multielectron to two-electron spin states and a subsequent two-electron spin readout, thus obviating the need to resolve dense multielectron energy levels. Using this technique, we measure the relaxations of the high-spin states and find them to be an order of magnitude faster than those of low-spin states. Numerical calculations of spin relaxation rates using the exact diagonalization method agree with the experiment. The technique developed here offers a new tool for the study and application of high-spin states in quantum dots.

Influence of Preoperative Difference in Lumbar Lordosis Between the Standing and Supine Positions on Clinical Outcomes After Single-level Transforaminal Lumbar Interbody Fusion: Minimum 2-year Follow-up

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

The aim of this study was to investigate whether a preoperative difference in lumbar lordosis (D-LL) between the standing and supine positions is associated with clinical outcomes after transforaminal lumbar interbody fusion (TLIF).

SUMMARY OF BACKGROUND DATA

Several factors have been reported to be associated with surgical outcomes after TLIF. However, the association between preoperative D-LL and clinical outcomes after TLIF is unknown.

METHODS

We enrolled 45 lumbar degenerative disease patients (mean age: 65.7 ± 11.3 years old; 24 males) treated with single-level TLIF. Surgical outcomes were assessed using Oswestry disability index, visual analog scale (VAS; low back pain [LBP], lower-extremity pain, numbness, LBP in motion, in standing, and in sitting), Japanese Orthopaedic Association Back Pain Evaluation Questionnaire, Japanese Orthopaedic Association score for intermittent claudication (JOA score), and Nakai's scoring system. The preoperative D-LL between the standing radiograph and computed tomography (CT) in the supine position was defined as LL in supine CT-standing radiograph. Patients were divided into two groups according to D-LL value (D-LL >-4°, and D-LL ≤-4°). Clinical outcomes were compared between the groups, and correlations between preoperative D-LL and clinical outcomes were analyzed.

RESULTS

There were no significant differences in preoperative clinical parameters between the two groups. Postoperative VASs for lower extremity pain, numbness, LBP in standing, and JOA score in D-LL >-4° group were significantly worse than in the D-LL ≤-4° group (P < 0.05). Preoperative D-LL showed a weak correlation with postoperative lower extremity pain and numbness (P < 0.05).

CONCLUSION

This study revealed that lumbar degenerative disease patients, who have greater preoperative kyphotic lumbar alignment in the standing versus supine position, tend to have postoperative residual symptoms after TLIF. A preoperative comparison of lateral radiographs between the standing and supine positions is useful to predict patients' postoperative residual symptoms.Level of Evidence: 3.

Fine Tunable, Redox Active Octapalladium Chains Supported by Linear Tetraphosphines, Leading to Dynamically 1D Self-Assembled Coordination Polymers

A series of the octapalladium chains supported by meso-Ph₂ PCH₂ P(Ph)CH₂ P(Ph)CH₂ PPh₂ (meso-dpmppm) ligands, [Pd₈ (meso-dpmppm)₄ (L)₂ ](BF₄ )₄ (L=none (1), solvents: CH₃ CN (2 a), dmf (2 b), dmso (2 c), RN≡C: R=Xyl (3 a), Mes (3 b), Dip (3 c), ^t Bu (3 d), Cy (3 e), CH₃ (CH₂ )₇ (3 f), CH₃ (CH₂ )₁₁ (3 g), CH₃ (CH₂ )₁₇ (3 h)) and [Pd₈ (meso-dpmppm)₄ (X)₂ ](BF₄ )₂ (X=Cl (4 a), N₃ (4 b), CN (4 c), SCN (4 d)), were synthesized by using 2 a as a stable good precursor, and characterized by spectroscopic (IR, ¹ H and ³¹ P NMR, UV-vis-NIR, ESI-MS) measurements and X-ray crystallographic analyses (for 1, 2 a, b, 3 a, b, e, f, 4 a-d). On the basis of DFT calculations on the X-ray determined structure of 2 b ([2b-Pd₈ ]⁴⁺ ) and the optimized models [Pd₈ (meso-Ph₂ PCH₂ P(H)CH₂ P(H)CH₂ PH₂ )₄ (CH₃ CN)₂ ]⁴⁺ ([Pd₈ Ph₈ ]⁴⁺ ) and [Pd₈ (meso-H₂ PCH₂ P(H)CH₂ P(H)CH₂ PH₂ )₄ (CH₃ CN)₂ ]⁴⁺ ([Pd₈ H₈ ]⁴⁺ ), with and without empirically calculating dispersion force stabilization energy (B3LYP-D3, B3LYP), the formation energy between the two Pd₄ fragments is assumed to involve mainly noncovalent interactions (ca. -70 kcal/mol) with four sets of interligand C-H/π interactions and Pd⋅⋅⋅Pd metallophilic one, while electron shared covalent interactions are almost canceled out within the Pd₈ chain. All the compounds isolated are stable in solution and exhibit characteristic absorption at ∼900 nm, which is assignable to a spin allowed HOMO to LUMO transition, and shows temperature dependent intensity change with variable absorption coefficients presumably due to coupling with some thermal vibrations. The structures and electronic states of the Pd₈ chains are found finely tunable by varying the terminal capping ligands. In particular, theoretical calculations elucidated that the HOMO-LUMO energy gap is systematically related to the central Pd-Pd distance (2.7319(6)-2.7575(6) Å) by two ways with neutral ligands L (1, 2, 3) and with anionic ligands X (4), which are reflected on the NIR absorption energy of 867-954 nm. The isocyanide terminated Pd₈ complexes (3) further reacted with excess of RNC (6 eq) to afford the Pd₄ complexes, [Pd₄ (meso-dpmppm)₂ (RNC)₂ ](BF₄ )₂ (13), and the cyclic voltammograms of 2 a (L=CH₃ CN), 3, and 13 (R=Xyl, Mes, ^t Bu, Cy) demonstrated wide range redox behaviors from 2{Pd₄ }⁴⁺ to 2{Pd₄ }⁰ through 2{Pd₄ }²⁺ ↔{Pd₈ }⁴⁺ , {Pd₈ }³⁺ , and {Pd₈ }²⁺ strings. The oxidized complexes, [Pd₄ (meso-dpmppm)₂ (RNC)₃ ](BF₄ )₄ (16), were characterized by X-ray analyses, and the two-electron reduced chain of [Pd₈ (meso-dpmppm)₄ ](BF₄ )₂ (7) was analyzed by spectroscopic and electrochemical techniques and DFT calculations. Reactions of 2 a with 1 equiv. of aromatic linear bisisocyanide (BI) in CH₂ Cl₂ deposited insoluble coordination polymers, {[Pd₈ (meso-dpmppm)₄ (BI)](BF₄ )₄ }_n (5), and interestingly, they were soluble in acetonitrile, ³¹ P{¹ H} and ¹ H DOSY NMR spectra as well as SAXS curves suggesting that the coordination polymers may exist in acetonitrile as dynamically 1D self-assembled coordination polymers comprising ca. 50 units of the Pd₈ rod averaged within the timescale.

POS1487-HPR NEXT-GENERATION ONLINE TELEMEDICINE SYSTEM UTILIZING MIXED REALITY FOR RHEUMATOID ARTHRITIS

Background:

Telemedicine can be performed using a conventional videophone or web conferencing system. Then, joint lesions can only be observed and inferred from two-dimensional images, and it is difficult to perform accurate joint assessments, which is essential for the management of rheumatoid arthritis (RA).

Objectives:

To develop the next-generation online telemedicine system utilizing mixed reality for RA.

Methods:

We have developed a system that can assess joints accurately in three-dimensions images in real-time, using Azure Kinect DK (depth sensor)/ HoloLens 2 (headset), which are mixed reality technologies, and Teams (online interview/chat) provided by Microsoft. Furthermore, by applying artificial intelligence (AI), we plan to implement additionally to this system 1) a function to quickly catch and automatically evaluate the patient’s anxiety and changes in facial expressions at the time of examination, 2) a function to record dialogue with the patient in chronological order, 3) a function to support the detection of swollen joints, and 4) function to automatically analyze the questionnaire.

Results:

This system remotely connects a rheumatologist in the Nagasaki University Hospital (Nagasaki City, urban area) and a patient with RA and a non- rheumatologist in the Goto Central Hospital (Goto Island, rural area). A three-dimensional hologram of the patient’s hand projected in front of a rheumatologist. Using this system, we are able to evaluate joints more accurately than using a conventional videophone or web conferencing system.

Conclusion:

It is expected that this system will enable remote medical care specializing in rheumatology, which is standardized at a high level even in areas without rheumatologists such as remote islands and remote areas. This system remotely connects Nagasaki City and Goto Island, but due to the performance of the system, it is not limited to these areas and it is possible to connect rheumatologists to any area that can be connected to the network. It is also effective for the purpose of avoiding the risk of infection during long-distance hospital visits under the epidemic of COVID-19 infection.

References:

[1]Mov Disord. 2020;35:1719-1720.

Disclosure of Interests:

Shin-ya Kawashiri Speakers bureau: Speaker fees from AbbVie, Asahi Kasei, Astellas, Chugai, Eisai, Eli Lilly, Mitsubishi Tanabe, Novartis, and ONO., Grant/research support from: Research grants from Pfizer., Fumiaki Nonaka: None declared, Shinji Chiba: None declared, Tomoyuki Honda: None declared, Tomohiko Nakajima: None declared, Tomoyuki Ishikawa: None declared, Atsushi Kawakami Speakers bureau: Speaker fees from AbbVie, Actelion, Asahi Kasei, Astellas, Boehringer Ingelheim, Celltrion, Chugai, Daiichi Sankyo, Eisai, Eli Lilly, GSK, Janssen, Kowa, MedPeer, Mitsubishi Tanabe, Novartis, ONO, Pfizer, Taisho, and Takeda., Grant/research support from: Grants and research support from AbbVie, Actelion, Asahi Kasei, Astellas, AYUMI, Boehringer Ingelheim, Bristol-Myers Squibb, Celltrion, Chugai, Daiichi Sankyo, Eisai, Eli Lilly, Kyowa Hakko Kirin, MSD, Neopharma, Novartis, ONO, Sanofi, Taisho, Takeda Science Foundation, and Teijin