Effects of empagliflozin on progression of chronic kidney disease: a prespecified secondary analysis from the empa-kidney trial

BACKGROUND

Sodium-glucose co-transporter-2 (SGLT2) inhibitors reduce progression of chronic kidney disease and the risk of cardiovascular morbidity and mortality in a wide range of patients. However, their effects on kidney disease progression in some patients with chronic kidney disease are unclear because few clinical kidney outcomes occurred among such patients in the completed trials. In particular, some guidelines stratify their level of recommendation about who should be treated with SGLT2 inhibitors based on diabetes status and albuminuria. We aimed to assess the effects of empagliflozin on progression of chronic kidney disease both overall and among specific types of participants in the EMPA-KIDNEY trial.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA), and included individuals aged 18 years or older with an estimated glomerular filtration rate (eGFR) of 20 to less than 45 mL/min per 1·73 m2, or with an eGFR of 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher. We explored the effects of 10 mg oral empagliflozin once daily versus placebo on the annualised rate of change in estimated glomerular filtration rate (eGFR slope), a tertiary outcome. We studied the acute slope (from randomisation to 2 months) and chronic slope (from 2 months onwards) separately, using shared parameter models to estimate the latter. Analyses were done in all randomly assigned participants by intention to treat. EMPA-KIDNEY is registered at ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and then followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroups of eGFR included 2282 (34·5%) participants with an eGFR of less than 30 mL/min per 1·73 m2, 2928 (44·3%) with an eGFR of 30 to less than 45 mL/min per 1·73 m2, and 1399 (21·2%) with an eGFR 45 mL/min per 1·73 m2 or higher. Prespecified subgroups of uACR included 1328 (20·1%) with a uACR of less than 30 mg/g, 1864 (28·2%) with a uACR of 30 to 300 mg/g, and 3417 (51·7%) with a uACR of more than 300 mg/g. Overall, allocation to empagliflozin caused an acute 2·12 mL/min per 1·73 m2 (95% CI 1·83-2·41) reduction in eGFR, equivalent to a 6% (5-6) dip in the first 2 months. After this, it halved the chronic slope from -2·75 to -1·37 mL/min per 1·73 m2 per year (relative difference 50%, 95% CI 42-58). The absolute and relative benefits of empagliflozin on the magnitude of the chronic slope varied significantly depending on diabetes status and baseline levels of eGFR and uACR. In particular, the absolute difference in chronic slopes was lower in patients with lower baseline uACR, but because this group progressed more slowly than those with higher uACR, this translated to a larger relative difference in chronic slopes in this group (86% [36-136] reduction in the chronic slope among those with baseline uACR <30 mg/g compared with a 29% [19-38] reduction for those with baseline uACR ≥2000 mg/g; ptrend<0·0001).

INTERPRETATION

Empagliflozin slowed the rate of progression of chronic kidney disease among all types of participant in the EMPA-KIDNEY trial, including those with little albuminuria. Albuminuria alone should not be used to determine whether to treat with an SGLT2 inhibitor.

FUNDING

Boehringer Ingelheim and Eli Lilly.

Variability in sonographic anterior drawer test measurements of the ankle: Experienced versus beginner examiners

BACKGROUND

This study aimed to clarify the variability in the measurements of stress sonography of the ankle and determine the effects of examiner experience on the measurements.

METHODS

Twenty examiners (10 experienced and 10 beginners) were included in the study. Each examiner performed stress ultrasonography on a patient with a chronic anterior talofibular ligament injury and a patient with an intact ligament using the reverse anterior drawer method. Changes in ligament length before versus after stress were determined. The same 20 examiners performed ultrasonography on two other patients with an injured or intact ATFL using the anterior drawer method. The length change values and variance were compared between the groups using t-tests and F-tests.

RESULTS

Using the reverse anterior drawer method, the change in the anterior talofibular ligament length was 3.3 mm (range, 2.2-4.8 mm) in the experienced group and 2.7 mm (0.0-4.1 mm) in the beginner group for the ligament injured patient. The length changes for the patient with intact anterior talofibular ligament were 0.5 mm (0.1-0.9 mm) and 0.4 mm (-0.1-1.5 mm) in the experienced and beginner groups, respectively. There were no significant intergroup differences in measurement amount (P = 0.37) or variance (P = 0.72). Similarly, using the anterior drawer method, no significant differences between the groups were found in measurement amount or variance.

CONCLUSION

The quantitative evaluation of stress sonography of the ankle was variable regardless of examiner experience or stress method, particularly in patients with an anterior talofibular ligament injury. The amount of variability appeared to be unacceptably large for clinical application. Our study results highlight the need for technical standardization.

Impact of primary kidney disease on the effects of empagliflozin in patients with chronic kidney disease: secondary analyses of the EMPA-KIDNEY trial

BACKGROUND

The EMPA-KIDNEY trial showed that empagliflozin reduced the risk of the primary composite outcome of kidney disease progression or cardiovascular death in patients with chronic kidney disease mainly through slowing progression. We aimed to assess how effects of empagliflozin might differ by primary kidney disease across its broad population.

METHODS

EMPA-KIDNEY, a randomised, controlled, phase 3 trial, was conducted at 241 centres in eight countries (Canada, China, Germany, Italy, Japan, Malaysia, the UK, and the USA). Patients were eligible if their estimated glomerular filtration rate (eGFR) was 20 to less than 45 mL/min per 1·73 m2, or 45 to less than 90 mL/min per 1·73 m2 with a urinary albumin-to-creatinine ratio (uACR) of 200 mg/g or higher at screening. They were randomly assigned (1:1) to 10 mg oral empagliflozin once daily or matching placebo. Effects on kidney disease progression (defined as a sustained ≥40% eGFR decline from randomisation, end-stage kidney disease, a sustained eGFR below 10 mL/min per 1·73 m2, or death from kidney failure) were assessed using prespecified Cox models, and eGFR slope analyses used shared parameter models. Subgroup comparisons were performed by including relevant interaction terms in models. EMPA-KIDNEY is registered with ClinicalTrials.gov, NCT03594110.

FINDINGS

Between May 15, 2019, and April 16, 2021, 6609 participants were randomly assigned and followed up for a median of 2·0 years (IQR 1·5-2·4). Prespecified subgroupings by primary kidney disease included 2057 (31·1%) participants with diabetic kidney disease, 1669 (25·3%) with glomerular disease, 1445 (21·9%) with hypertensive or renovascular disease, and 1438 (21·8%) with other or unknown causes. Kidney disease progression occurred in 384 (11·6%) of 3304 patients in the empagliflozin group and 504 (15·2%) of 3305 patients in the placebo group (hazard ratio 0·71 [95% CI 0·62-0·81]), with no evidence that the relative effect size varied significantly by primary kidney disease (pheterogeneity=0·62). The between-group difference in chronic eGFR slopes (ie, from 2 months to final follow-up) was 1·37 mL/min per 1·73 m2 per year (95% CI 1·16-1·59), representing a 50% (42-58) reduction in the rate of chronic eGFR decline. This relative effect of empagliflozin on chronic eGFR slope was similar in analyses by different primary kidney diseases, including in explorations by type of glomerular disease and diabetes (p values for heterogeneity all >0·1).

INTERPRETATION

In a broad range of patients with chronic kidney disease at risk of progression, including a wide range of non-diabetic causes of chronic kidney disease, empagliflozin reduced risk of kidney disease progression. Relative effect sizes were broadly similar irrespective of the cause of primary kidney disease, suggesting that SGLT2 inhibitors should be part of a standard of care to minimise risk of kidney failure in chronic kidney disease.

FUNDING

Boehringer Ingelheim, Eli Lilly, and UK Medical Research Council.

Do standardization of the procedure reduce measurement variability of the sonographic anterior drawer test of the ankle?

BACKGROUND

In quantitative ankle stress sonography, different examiners use different techniques, which may cause measurement variability. This study aimed to clarify whether standardizing stress sonography techniques reduces variability in the quantitative measurement of anterior talofibular ligament length change.

METHODS

Fourteen examiners with a mean ultrasound experience of 8.7 years participated in this study. Each examiner performed stress ultrasonography of the ankle using their preferred method on one patient with an intact anterior talofibular ligament (Patient 1) and on two patients with chronic ankle instability (Patient 2 and 3). Changes in the ligament length between the resting and stressed positions were determined. A consensus meeting was then conducted to standardize the sonographic technique, which was used by the examiners during a repeat stress sonography on the same patients. The variance and measured values were compared between the preferred and standardized techniques using F-tests and paired t-tests, respectively.

RESULTS

At a consensus meeting, a sonographic technique in which the examiner pushed the lower leg posteriorly against the fixed foot was adopted as the standardized technique. In Patient 1, the change in the anterior talofibular ligament length was 0.4 (range, -2.3-1.3) mm and 0.6 (-0.6-1.7) mm using the preferred and standardized techniques, respectively, with no significant difference in the variance (P = 0.51) or the measured value (P = 0.52). The length changes in Patient 2 were 2.0 (0.3-4.4) mm and 1.7 (-0.9-3.8) mm using the preferred and standardized techniques, respectively. In Patient 3, the length changes were 1.4 (-2.7-7.1) mm and 0.7 (-2.0-2.3) mm. There were no significant differences between the techniques in either patient group.

CONCLUSION

Variability in the quantitative measurement of ankle stress sonography was not reduced despite the standardization of the technique among examiners. Hence, comparing the measured values between different examiners should be avoided.

Validity of the Center-Center Method for the Syndesmotic Fixation Axis Compared to the Transsyndesmotic Axis

BACKGROUND

Placement of clamp forceps along the transsyndesmotic (TS) axis reduces the risk of iatrogenic syndesmotic malreduction during ankle fracture surgery with tibiofibular diastasis. This study aimed to measure the difference between the TS axis and the axis determined by an intraoperative fluoroscopic technique using the center-center (CC) method. We also compared the values obtained when the CC method was performed at different heights from the tibial plafond.

METHODS

We evaluated the computed tomography scans of 150 patients with normal syndesmosis. The CC method was simulated using digitally reconstructed radiographs. The TS and CC axes were projected onto an axial computed tomographic image linked to digitally reconstructed radiography. The angle between the two axes (interaxis angle) and the distance between the intersection of these axes and the medial tibial cortex (interaxis distance) were measured. The procedures were performed 0, 10, and 20 mm proximal to the tibial plafond, and the measurements were compared among the different heights using a 1-way repeated-measures analysis of variance.

RESULTS

The TS axis was found to be externally rotated to the CC axis, with an interaxis angle of 8.5 degrees (SD, 6.8 degrees). The interaxis angle increased from 1.9 degrees at a height of 0 mm to a greater angle at higher heights (P < .001). The overall interaxis distance was 7.7 (SD, 6.3) mm, increasing from 2.0 mm at a height of 0 mm to a greater distance at higher heights (P < .001).

CONCLUSION

The TS axis was externally rotated relative to the CC axis, and the difference between the 2 axes was greater when the CC method was performed on the higher heights from the tibial plafond. To clamp the syndesmosis along the TS axis, the CC method should be applied close to the ankle joint.

LEVEL OF EVIDENCE

Level IV, case series.

Internet search analysis on the treatment of rheumatoid arthritis: What do people ask and read online?

OBJECTIVES

This study aimed to characterize the content of frequently asked questions about the treatment of rheumatoid arthritis (RA) on the internet in Japan and to evaluate the quality of websites related to the questions.

METHODS

We searched terms on the treatment of RA on Google and extracted frequently asked questions generated by the Google "people also ask" function. The website that answered each question was also obtained. We categorized the questions based on the content. The quality of the websites was evaluated using the brief DISCERN, Journal of American Medical Association benchmark criteria, and Clear Communication Index.

RESULTS

Our search yielded 83 questions and the corresponding websites. The most frequently asked questions were regarding the timeline of treatment (n = 17, 23%) and those on the timeline of the clinical course (n = 13, 16%). The median score of brief DISCERN was 11 points, with only 7 (8%) websites having sufficient quality. Websites having sufficient quality based on the Journal of American Medical Association benchmark criteria and Clear Communication Index were absent.

CONCLUSIONS

The questions were most frequently related to the timeline of treatment and clinical course. Physicians should provide such information to patients with RA in the counseling and education materials.

Whole-genome sequencing analysis of molecular epidemiology and silent transmissions causing meticillin-resistant Staphylococcus aureus bloodstream infections in a university hospital

BACKGROUND

The emergence of novel genomic-type clones, such as community-associated meticillin-resistant Staphylococcus aureus (MRSA) and livestock-associated MRSA, and their invasion into hospitals have become major concerns worldwide; however, little information is available regarding the prevalence of MRSA in Japan. Whole-genome sequencing (WGS) has been conducted to analyse various pathogens worldwide. Therefore, it is important to establish a genome database of clinical MRSA isolates available in Japan.

AIM

A molecular epidemiological analysis of MRSA strains isolated from bloodstream-infected patients in a Japanese university hospital was conducted using WGS and single-nucleotide polymorphism (SNP) analysis. Additionally, through a review of patients' clinical characteristics, the effectiveness of SNP analysis as a tool for detecting silent nosocomial transmission that may be missed by other methods was evaluated in diverse settings and various time points of detection.

METHODS

Polymerase-chain-reaction-based staphylococcal cassette chromosome mec (SCCmec) typing was performed using 135 isolates obtained between 2014 and 2018, and WGS was performed using 88 isolates obtained between 2015 and 2017.

FINDINGS

SCCmec type II strains, prevalent in 2014, became rare in 2018, whereas the prevalence of SCCmec type IV strains increased from 18.75% to 83.87% of the population, and became the dominant clones. Clonal complex (CC) 5 CC8 and CC1 were detected between 2015 and 2017, with CC1 being dominant. In 88 cases, SNP analyses revealed nosocomial transmissions among 20 patients which involved highly homologous strains.

CONCLUSIONS

Routine monitoring of MRSA by whole-genome analysis is effective not only for gaining knowledge regarding molecular epidemiology, but also for detecting silent nosocomial transmission.

Differential Associations of Sports Participation With Self-Rated Health and Depressive Symptoms Among Japanese Adolescents

INTRODUCTION

We aimed to evaluate the associations of sports participation with self-rated health and depressive symptoms in a nationally representative sample of Japanese adolescents.

METHODS

A questionnaire survey was conducted with 1,658 adolescents aged between 12 and 21 years. Sports participation levels were divided into high-frequency, moderate-frequency, low-frequency, and no-participation groups. Self-rated health was evaluated using a four-grade scale. Depressive symptoms were assessed using the Japanese version of the Patient Health Questionnaire-8. Other lifestyle behaviors were also surveyed. The associations of sports participation with self-rated health and depressive symptoms were examined using multiple logistic regression analysis.

RESULTS

The participants in the high- (odds ratio (OR), 0.45) and moderate-frequency (OR, 0.46) groups were less likely to self-report poor health than those in the non-participation group. By contrast, a U-shaped association was found between sports participation and depression, in which the participants in the moderate-frequency group (OR, 0.52) were less likely to have depressive symptoms. The OR for the high- (0.89) and low-frequency (0.91) groups were not significant. Furthermore, eating regular breakfasts, six or more days/week, and having shorter screen times of less than two hours/day were negatively associated with poor self-reported health and depressive symptoms.

CONCLUSION

Moderate- to high-frequency sports activities are associated with a reduced risk of poor self-rated health among Japanese adolescents. However, only moderate-frequency activities were associated with a reduced risk of depression. Participation in optimal sports activities may effectively lower the risk of poor health in adolescents.

Referential values for lower limb flexibility in healthy children and adolescents in Japan: A five-year cross-sectional study

BACKGROUND

Lower limb flexibility (LLF) is an essential motor function. However, assessing LLF during adolescence is difficult because of the influence of marked physical changes. We, therefore, assessed LLF and investigated the relationship between LLF and sex and age in healthy children and adolescents.

METHODS

We conducted a five-year cross-sectional study with students aged 8-14 years at a single school in Japan. We evaluated the heel-buttock distance (HBD), straight leg raising angle (SLRA), and dorsiflexion angle of the ankle joint (DFA) at the beginning of each year. We conducted a comparative analysis on the performance of the HBD, SLRA, and DFA techniques, stratified by both sex and age. The statistical significance of observed differences was assessed through the application of Mann-Whitney U and Kruskal-Wallis tests. Furthermore, we analyzed the effects of sex, age, height, and weight on LLF using a multivariable linear regression model.

RESULTS

Of the 4221 initial study participants, 3370 were analyzed. Mean HBD, SLRA, and DFA values were 1.6 cm, 77.0°, and 15.7°, respectively. Girls showed significantly higher HBD and lower SLRA and DFA values than boys and 14-year-olds (p < 0.01). Median HBD value for girls was 0 cm, whereas for boys, it exceeded 0 cm after age 13. The median SLRA value for girls was 80-85°, while for boys, it was 70-75°. The median DFA value for girls was 15-19°, and for boys, it was 12-15°. A multivariable linear regression model indicated that boys had significantly greater tightness than girls (p < 0.01).

CONCLUSIONS

The reference values of HBD, SLRA, and DFA differed according to age and sex. Furthermore, we showed that sex differences were significantly associated with LLF. Data in this study provide the reference value for assessing LLF in children and adolescents.

Discovery of New Isotope ^{241}U and Systematic High-Precision Atomic Mass Measurements of Neutron-Rich Pa-Pu Nuclei Produced via Multinucleon Transfer Reactions

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

TRIM27 expression is associated with poor prognosis in sinonasal mucosal melanoma

BACKGROUND

Tripartite motif-containing 27 (TRIM27) has been implicated in the progression of various cancers. However, the role of TRIM27 in sinonasal mucosal melanoma (SNMM) remains poorly understood.

MATERIALS & METHODS

We retrospectively examined 28 patients with SNMM treated with between 2003 and 2021. We undertook immunohistochemical analysis of TRIM27, Ki-67, and p-Akt1 expression in SNMM tissues. We also investigated the relationship between TRIM27 expression and clinical characteristics, prognosis, Ki-67 as a tumor growth potential marker, and p-Akt1 as one of the prognostic factors in mucosal melanoma.

RESULTS

TRIM27 expression was significantly higher in T4 disease than in T3 disease and was higher in stage IV than in stage III. Patients with high-TRIM27 SNMM had a significantly poorer prognosis in terms of overall survival (OS) and disease-free survival.There was also a significantly higher rate of distant metastasis. Univariate analysis for OS revealed that TRIM27 and T classification were significant poor prognostic factors. In addition, the Ki-67 positive score and the p-Akt1 total staining score were significantly higher in the high-TRIM27 group than in the low-TRIM27 group.

CONCLUSIONS

High TRIM27 expression in SNMM was associated with advanced T classification, poor prognosis and distant metastasis. We suggest that TRIM27 has potential as a novel biomarker for prognosis in SNMM.

Impact of pain in other body regions on the foot-specific quality of life in patients with hallux valgus

OBJECTIVES

The purpose of this study was to clarify the prevalence of pain outside the foot, and to determine the associations of pain outside the foot with foot-specific quality of life (QOL) in patients with hallux valgus.

METHODS

Patients scheduled to undergo hallux valgus surgery were recruited. Patients answered whether they experienced disabling pain in 13 body regions other than the foot. Foot-specific QOLwas assessed using the Self-Administered Foot Evaluation questionnaire (SAFE-Q). Foot pain was quantified using the visual analogue scale (VAS). Patient characteristics, including age, sex, comorbidity, anxiety, and depression, were also surveyed. The association between pain elsewhere and the SAFE-Q and pain VAS scores were assessed using univariate and multivariate analyses.

RESULTS

Of 102 patients, 55 (54%) experienced pain other than the foot. All SAFE-Q subscale scores were lower, and pain VAS was higher in patients with pain elsewhere than in patients without. In the multivariate analysis, an increase in the number of pain regions was independently associated with a decrease in SAFE-Q scores and an increase in pain VAS.

CONCLUSION

More than half of the patients with hallux valgus experienced pain elsewhere. The presence of pain elsewhere was associated with poorer foot-specific QOL and severer foot pain.

Protective effect of the tunneling nanotube-TNFAIP2/M-sec system on podocyte autophagy in diabetic nephropathy

Podocyte injury leading to albuminuria is a characteristic feature of diabetic nephropathy (DN). Hyperglycemia and advanced glycation end products (AGEs) are major determinants of DN. However, the underlying mechanisms of podocyte injury remain poorly understood. The cytosolic protein TNFAIP2/M-Sec is required for tunneling nanotubes (TNTs) formation, which are membrane channels that transiently connect cells, allowing organelle transfer. Podocytes express TNFAIP2 and form TNTs, but the potential relevance of the TNFAIP2-TNT system in DN is unknown. We studied TNFAIP2 expression in both human and experimental DN and the renal effect of tnfaip2 deletion in streptozotocin-induced DN. Moreover, we explored the role of the TNFAIP2-TNT system in podocytes exposed to diabetes-related insults. TNFAIP2 was overexpressed by podocytes in both human and experimental DN and exposre of podocytes to high glucose and AGEs induced the TNFAIP2-TNT system. In diabetic mice, tnfaip2 deletion exacerbated albuminuria, renal function loss, podocyte injury, and mesangial expansion. Moreover, blockade of the autophagic flux due to lysosomal dysfunction was observed in diabetes-injured podocytes both in vitro and in vivo and exacerbated by tnfaip2 deletion. TNTs allowed autophagosome and lysosome exchange between podocytes, thereby ameliorating AGE-induced lysosomal dysfunction and apoptosis. This protective effect was abolished by tnfaip2 deletion, TNT inhibition, and donor cell lysosome damage. By contrast, Tnfaip2 overexpression enhanced TNT-mediated transfer and prevented AGE-induced autophagy and lysosome dysfunction and apoptosis. In conclusion, TNFAIP2 plays an important protective role in podocytes in the context of DN by allowing TNT-mediated autophagosome and lysosome exchange and may represent a novel druggable target.Abbreviations: AGEs: advanced glycation end products; AKT1: AKT serine/threonine kinase 1; AO: acridine orange; ALs: autolysosomes; APs: autophagosomes; BM: bone marrow; BSA: bovine serum albumin; CTSD: cathepsin D; DIC: differential interference contrast; DN: diabetic nephropathy; FSGS: focal segmental glomerulosclerosis; HG: high glucose; KO: knockout; LAMP1: lysosomal-associated membrane protein 1; LMP: lysosomal membrane permeabilization; MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; PI3K: phosphoinositide 3-kinase; STZ: streptozotocin; TNF: tumor necrosis factor; TNFAIP2: tumor necrosis factor, alpha-induced protein 2; TNTs: tunneling nanotubes; WT: wild type.

Study of the N=32 and N=34 Shell Gap for Ti and V by the First High-Precision Multireflection Time-of-Flight Mass Measurements at BigRIPS-SLOWRI

The atomic masses of ^{55}Sc, ^{56,58}Ti, and ^{56-59}V have been determined using the high-precision multireflection time-of-flight technique. The radioisotopes have been produced at RIKEN's Radioactive Isotope Beam Factory (RIBF) and delivered to the novel designed gas cell and multireflection system, which has been recently commissioned downstream of the ZeroDegree spectrometer following the BigRIPS separator. For ^{56,58}Ti and ^{56-59}V, the mass uncertainties have been reduced down to the order of 10 keV, shedding new light on the N=34 shell effect in Ti and V isotopes by the first high-precision mass measurements of the critical species ^{58}Ti and ^{59}V. With the new precision achieved, we reveal the nonexistence of the N=34 empirical two-neutron shell gaps for Ti and V, and the enhanced energy gap above the occupied νp_{3/2} orbit is identified as a feature unique to Ca. We perform new Monte Carlo shell model calculations including the νd_{5/2} and νg_{9/2} orbits and compare the results with conventional shell model calculations, which exclude the νg_{9/2} and the νd_{5/2} orbits. The comparison indicates that the shell gap reduction in Ti is related to a partial occupation of the higher orbitals for the outer two valence neutrons at N=34.

Foot morphology and correlation with lower extremity pain in Japanese children: A cross-sectional study of the foot posture Index-6

BACKGROUND

Abnormal foot morphology in children and adolescents is a possible risk factor for lower extremity pain. Foot posture index-6 (FPI-6) is a valid and reliable tool to assess foot morphology. However, the normative data on the age distribution for FPI-6 in Asian children and adolescents are still minimal. Further, the correlation of FPI-6 with lower extremity pain is poorly understood. We aimed to investigate the normative distribution for FPI-6 and the relationship between FPI-6 scores and knee and heel pain in Japanese children.

METHODS

We included 2569 Japanese children, aged 9-15 years, at a single school from 2016 to 2018. We summarized the age distribution of children and their mean bilateral FPI-6 scores. Additionally, we assessed the tenderness at the apophysis or tendon insertions at the knee and heel. We performed a cross-sectional analysis to investigate the correlations between FPI-6 scores and sex, age, and knee and heel pain for the data obtained each year.

RESULTS

The mean FPI-6 score was 3.1 ± 2.4, 3.4 ± 2.0, and 3.2 ± 1.9 for the left foot and 3.0 ± 2.4, 3.2 ± 1.9, and 3.1 ± 1.9 for the right foot in 2016, 2017, and 2018, respectively. Boys tended to have higher scores than girls, and the FPI-6 score of the left foot was significantly higher than that of the right foot (p < 0.05). There was no correlation between FPI-6 scores and knee and heel pain.

CONCLUSION

Children and adolescents between 9 and 15 years of age have neutral to slightly pronated foot morphology and an average FPI-6 score of 3.0-3.4. In addition, there was no relationship between foot morphology and knee and heel pain. This normative distribution for FPI-6 in Japanese children could serve as a reference value for future research and clinical evaluation.

Nonreciprocal Directional Dichroism in Magnetoelectric Spin Glass

Optical absorption spectra in the visible and near-infrared light were measured for magnetoelectric spin glass Ni_{0.4}Mn_{0.6}TiO_{3} under various field-cooled conditions. Despite the absence of long-range magnetic-dipole order, this spin-glass system exhibits nonreciprocal directional dichroism (NDD) at zero external field after a magnetoelectric field-cooled procedure. This result is distinct from previous studies on NDD in systems with magnetic toroidal moments induced either by long-range magnetic-dipole order or by applying crossed electric and magnetic fields. The present Letter conclusively demonstrates that the observed NDD originates from magnetoelectrically induced ferroic order of magnetic toroidal moments without conventional magnetic-dipole order.

Impact of Pain in Other Body Regions on the Foot-Specific Quality of Life in Patients with Hallux Valgus

Category:

Bunion

Introduction/Purpose:

The purpose of this study was to clarify the prevalence of pain outside the foot, and to determine the associations of pain outside the foot with foot-specific quality of life (QOL) in patients with hallux valgus.

Methods:

Patients scheduled to undergo surgery for idiopathic hallux valgus (rheumatoid forefoot deformity not included) were recruited. Patients less than 20 years old, and those with a history of foot and ankle surgery were excluded. Patients answered whether they experienced disabling pain in 13 body regions other than the foot. Foot-specific QOL was assessed using the Self- Administered Foot Evaluation questionnaire (SAFE-Q). Foot pain was quantified using the visual analogue scale (VAS). Patient characteristics, including age, sex, comorbidity, anxiety, and depression, were also surveyed. The association between pain elsewhere and the SAFE-Q and pain VAS scores were assessed using univariate and multivariate analyses.

Results:

Of 102 patients, 55 (54%) experienced pain other than the foot. All SAFE-Q subscale scores were lower, and pain VAS was higher in patients with pain elsewhere than in patients without. In the multivariate analysis, an increase in the number of pain regions was independently associated with a decrease in SAFE-Q scores and an increase in pain VAS.

Conclusion:

More than half of the patients with hallux valgus experienced pain elsewhere. The presence of pain elsewhere was associated with poorer foot-specific QOL and severer foot pain. Assessment of pain elsewhere is necessary to evaluate foot- specific QOL in HV patients.

Nuclear receptor subfamily 1 group D member 1 in the pathology of obesity-induced osteoarthritis progression

Mechanical overload and chemical factors are both related to obesity-induced progression of knee osteoarthritis. The circadian rhythm is related to the development of metabolic syndrome and the progression of osteoarthritis, and the core clock genes nuclear receptor subfamily 1 group D member 1 (NR1D1) and brain and muscle arnt-like protein 1 (BMAL1) are dysregulated in cartilage from patients with osteoarthritis. Here, we focused on NR1D1 and investigated osteoarthritis-related changes and gene expression in a mouse model of diet-induced obesity. A high-fat diet was provided to C57BL6/J mice, and changes in body weight, blood lipids, and gene expression were investigated. Destabilization of the medial meniscus or sham surgery was performed on mice fed a high-fat diet or normal diet, and histological osteoarthritis-related changes and NR1D1 expression were investigated. The effects of the NR1D1 agonist SR9009 were also assessed. Mice fed a high-fat diet developed significant obesity and dyslipidemia. Nr1d1 and Bmal1 gene expression levels decreased in the liver and knee joints. Moreover, increased osteoarthritis progression and decreased NR1D1 protein expression were observed in high-fat diet-fed mice after surgical osteoarthritis induction. SR9009 decreased the progression of obesity, dyslipidemia, and osteoarthritis. Overall, obesity and dyslipidemia induced by the high-fat diet led to osteoarthritis progression and decreased NR1D1 expression. Thus, NR1D1 may play an important role in obesity-induced osteoarthritis.

Cross-cultural Adaptation and Validation of the Japanese Version of the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS)

Background:

The Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) is a specifically designed scoring system for children and has been translated into several languages. However, to date, no validated Japanese version of this scoring system is available.

Purpose:

To translate the HSS Pedi-FABS into Japanese and assess its reliability and validity.

Study Design:

Cohort study (diagnosis); Level of evidence, 2.

Methods:

The HSS Pedi-FABS was translated into Japanese and back-translated into English to confirm the appropriateness of the translation. A total of 764 children aged 9 to 15 years participated in the validation study. The participants answered the Japanese version of the HSS Pedi-FABS along with 2 other questionnaires in Japanese (the Physical Activity Questionnaire for Older Children [PAQ-C] and the physical activity questionnaire of the World Health Organization’s Health Behavior in School-aged Children [HBSC PAQ]). At 1 month after the first assessment, the children answered the Japanese version of the HSS Pedi-FABS again. We evaluated reliability using the Cronbach alpha and the intraclass correlation coefficient. Validity was evaluated by quantifying floor and ceiling effects, correlations between the HSS Pedi-FABS and the PAQ-C, the HSS Pedi-FABS discrepancy between active and inactive groups divided by the HBSC PAQ, and correlation between the HSS Pedi-FABS and body mass index.

Results:

HSS Pedi-FABS scores were slightly but significantly higher in male participants (mean = 16.7) than in female participants (mean = 13.2). The Cronbach alpha coefficient was .90, and the intraclass correlation coefficient value was 0.90, indicating excellent internal consistency and test-retest reliability, respectively. No floor (2.6%) or ceiling effect (1.0%) was observed. The HSS Pedi-FABS was significantly correlated with the PAQ-C (r = 0.70). The active group demonstrated a significantly higher score on the HSS Pedi-FABS (mean = 18.9) than did the inactive group (mean = 11.2). In terms of discriminative validity, the HSS Pedi-FABS was not correlated with body mass index (r = –0.15).

Conclusion:

The Japanese version of the HSS Pedi-FABS demonstrated appropriate reliability and validity, indicating that it is a useful tool to assess physical activity levels in Japanese children.

HIF-2α Inhibits Ameloblast Differentiation via Hey2 in Tooth Development

Enamel is the highly mineralized outer layer of teeth; the cells responsible for enamel formation are ameloblasts. Local hypoxia and hypoxia inducible factor (HIF) in embryonic tissues are important to promote normal organogenesis. However, hypoxic state in tooth germs and the roles of HIF in ameloblast differentiation have not been understood. The aim of this study is to clarify the role of HIF in ameloblast differentiation during tooth germ development. We found that tooth germs were under hypoxia and HIF-1α and HIF-2α were expressed in tooth germs in embryonic mice. Then, we used HIF inhibitors to evaluate the function of HIF during tooth germ development. The HIF-2α inhibitor significantly decreased the size of tooth germs in organ culture, while the HIF-1α inhibitor did not apparently affect the size of tooth germs. The HIF-2α inhibitor enhanced the expression of amelogenin, a marker of ameloblast differentiation, in the tooth germs in organ culture and rat dental epithelial SF2 cells. Moreover, we found that the HIF-2α inhibitor-stimulating amelogenin expression was regulated by hes-related family basic helix-loop-helix transcription factor with YRPW motif 2(Hey2) in SF2 cells. These findings suggest that the HIF-2α-Hey2 axis plays an important role in ameloblast differentiation during tooth germ development.

The influence of COVID-19 pandemic on the incidence of knee pain and physical activity level in children and adolescents in Japan: A prospective observation study

BACKGROUND

The coronavirus disease 2019 (COVID-19) pandemic has had a profound impact on children's lifestyles. Some studies have reported psychological changes in children after the pandemic, but information on musculoskeletal problems is scarce. This study aimed to investigate the incidence of knee pain and changes in physical activity after the spread of COVID-19 among elementary and junior high school students in Japan.

METHODS

Knee pain and amount of physical activity were recorded on a monthly basis between August 2019 and February 2021 in children aged 8-14 years using a self-administered questionnaire. The amount of physical activity was scored using the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS). The period until February 2020 was defined as "Before pandemic," and the period from March 2020 was defined as "After pandemic." The incidences of knee pain and HSS Pedi-FABS scores before and after the COVID-19 pandemic were compared. Additionally, we compared the prevalence of knee pain and HSS Pedi-FABS scores according to sex and age.

RESULTS

We enrolled 886 and 881 participants before and after the pandemic, respectively. The prevalence of knee pain among the participants before and after the pandemic was 6.7% and 7.9%, respectively (p = 0.032). The mean HSS Pedi-FABS scores before and after the pandemic were 14.8 and 14.5, respectively (p = 0.005). Participants aged 14 years had a significantly lower incidence of knee pain (p = 0.013) and significantly higher HSS Pedi-FABS scores (p < 0.001) after the spread of COVID-19.

CONCLUSIONS

In elementary and junior high school students, increase in the incidence of knee pain and decrease in the amount of physical activity after the spread of COVID-19 were observed.

Automated detection of anterior cruciate ligament tears using a deep convolutional neural network

Background

The development of computer-assisted technologies to diagnose anterior cruciate ligament (ACL) injury by analyzing knee magnetic resonance images (MRI) would be beneficial, and convolutional neural network (CNN)-based deep learning approaches may offer a solution. This study aimed to evaluate the accuracy of a CNN system in diagnosing ACL ruptures by a single slice from a knee MRI and to compare the results with that of experienced human readers.

Methods

One hundred sagittal MR images from patients with and without ACL injuries, confirmed by arthroscopy, were cropped and used for the CNN training. The final decision by the CNN for intact or torn ACL was based on the probability of ACL tear on a single MRI slice. Twelve board-certified physicians reviewed the same images used by CNN.

Results

The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the CNN classification was 91.0%, 86.0%, 88.5%, 87.0%, and 91.0%, respectively. The overall values of the physicians’ readings were similar, but the specificity was lower than the CNN classification for some of the physicians, thus resulting in lower accuracy for the human readers.

Conclusions

The trained CNN automatically detected the ACL tears with acceptable accuracy comparable to that of human readers.

InP nanowire light-emitting diodes with different pn-junction structures

We report on the characterization of wurtzite (WZ) InP nanowire (NW) light-emitting diodes (LEDs) with different pn junctions (axial and radial). The series resistance tended to be smaller in the NW-LED using core-shell InP NWs with a radial pn junction than in the NW-LED using InP NWs with an axial pn junction, indicating that radial pn junctions are more suitable for current injection. The electroluminescence (EL) properties of both NW LEDs revealed that the EL had three peaks originating from the zinc-blende (ZB) phase, WZ phase, and ZB/WZ heterojunction. Transmission electron microscopy showed that the dominant EL in the radial pn junction originated from the ZB/WZ interface across the stacking faults.

Risk factors for the occurrence and protraction of patellar and patellar tendon pain in children and adolescents: a prospective cohort study of 3 years

Background

Patellar and patellar tendon pain is a common limitation to children’s participation in social and physical activities. Some factors have been implicated in the occurrence and protraction of knee pain, but the causal relationship is unknown. The purpose of this study was to investigate whether participants’ physical characteristics and activity level are risk factors for the occurrence and protraction of patellar and patellar tendon pain in children and adolescents.

Methods

A three-year prospective cohort study was conducted with healthy students who were aged 8–14 years old, in Japan. Height, weight, heel-buttock distance, straight leg raising angle, and dorsiflexion angle of the ankle joint were collected as individual physical factors at the beginning of each year. The presence of self-reported patellar and patellar tendon pain and the Hospital for Special Surgery Pediatric Functional Activity Brief Scale (HSS Pedi-FABS) was collected every month. Protraction was defined as either (1) pain lasting for more than three continuous months or (2) recurrent pain after more than three months of complete recovery. Participants who did not have any pain at the beginning of the observation period were included in the analysis. We analyzed the odds ratio (OR) of pain occurrence within a year of registration and protraction throughout the study period for all physical factors and HSS Pedi-FABS.

Results

We included 1133 participants in the analysis and 252 participants developed knee pain within a year. 34.8% of participants with pain experienced protraction during the follow-up period. A high HSS Pedi-FABS significantly predicted knee pain occurrence (OR 1.03, 95% confidence interval [CI] 1.01–1.05) and protraction (OR 1.03, 95% CI 1.00–1.05). In addition, younger children and girls were at a significantly higher risk of patellar and patellar tendon pain protraction (age, OR 0.81, 95% CI, 0.73–0.90; sex, OR 1.69, 95% CI, 1.09–2.64). Other physical factors did not significantly predict the occurrence or protraction of knee pain.

Conclusions

This study showed that a greater physical activity level was a risk factor for the occurrence and protraction of patellar and patellar tendon pain in childhood. In addition, younger age and female sex predicted higher risk of protraction of pain.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05349-y.

Effect of kinematics on the torque/force generation, surface characteristics, and shaping ability of a nickel titanium rotary glide path instrument: an ex-vivo study

AIM

To evaluate the effect of various rotational motions on the torque/force generation, surface wear, and shaping ability of the ProGlider glide path instrument (Dentsply Sirona).

METHODOLOGY

Mesiobuccal and mesiolingual canals of mandibular molars were selected based on the canal volume, length, angle of curvature (25°-40°), and radius of curvature (4-8 mm) after micro-computed tomographic scanning. The samples were randomly assigned to four groups (n = 13, each) according to movement kinematics [continuous rotation (CR; 300 rpm), optimum torque reverse motion (OTR; 180° forward and 90° reverse when torque > 0.4 N·cm), time-dependent reciprocal motion (TmR; 180° forward and 90° reverse), and optimum glide path motion (OGP; a combination of 90° forward, 90° reverse, 90° forward, and 120° reverse)]. Instrumentation was performed with an automated root canal instrument and torque/force analysing device. Maximum torque/force values, canal volume changes, and canal-centring ratios at 1, 3, 5, and 7 mm were evaluated. Surface defects (pits, grooves, microcracks, blunt cutting edges, and disruption of cutting edges) and spiral distortion on the ProGlider instrument were scored at the tip and 5 mm short of the tip before and after five consecutive uses with scanning electron microscopy. The Kruskal-Wallis test followed by Dunn's post-test with Bonferroni correction and Wilcoxon signed-rank test were used to analyse the data (α = 0.05).

RESULTS

OGP generated significantly less clockwise torque and greater upward force than other groups (P < 0.05). OGP resulted in significantly fewer surface defects than CR (P < 0.05). In OGP and CR, the tip exhibited more surface defects than 5 mm short of the tip (P < 0.05). CR resulted in greater volume changes than OGP and TmR (P < 0.05) and greater centring ratios (i.e., more deviation) than OGP at 1 mm and OTR at 3 mm (P < 0.05).

CONCLUSIONS

Under laboratory conditions using the ProGlider instrument, OGP generated significantly less clockwise torque and greater upward force than the other rotatory motions. OGP generated fewer superficial defects than CR, and the three modes of reciprocal rotation better maintained the apical curvature of root canals than CR with the ProGlider instrument.

Prognostic value of machine learning for acute heart failure

Funding Acknowledgements

Type of funding sources: None.

Background

At onset of acute heart failure (AHF), various clinical fundamental parameters including vital sign, laboratory data, or initial treatment were investigated, and we can roughly estimate the prognosis. However, machine learning method for prediction of the prognosis was not studied.

Purpose

To elucidate prognostic value of machine learning for AHF comparing conventional statistical model.

Methods

We enrolled consecutive 300 patients with AHF (79.5 ± 12.1 years, 158 Males). Patients with acute coronary syndrome, mechanical circulatory support cases, and cardio-pulmonary arrest cases were excluded. The patients were randomly divided into 80% (240 cases) and 20% (60 cases), and the former was used as train data, and the latter as validation data. Objective variable was set as cardiac death in one year. First, logistic regression analysis with Akaike’s information criterion (AIC) was performed, and extracted predictive parameters. The predictive model for the cardiac prognosis was constructed by cut-off value of ROC curve analysis of propensity score was calculated. Next, machine learning (random forest method and deep learning) to build predictive model was performed with the predictors. Finally, accuracy of each predictive model was compared.

Results

Thirty cases showed cardiac death in one year. Logistic regression with AIC extracted 8  predictors, and the cut off-value of propensity score with the 6 parameters was 0.110. The accuracy was 0.714 and area under ROC (AUROC) was 0.836. Conversely, random forest method demonstrated the accuracy as 0.927, AUROC 0.860. On deep learning, the accuracy was 0.937 and AUROC 0.901. 

The top 4 high feature importance of random forest were Cl/red blood cell count/pH/Anion Gap. However, accuracy of those predictors was lower than that of machine learning.

Conclusion

Machine learning was a powerful tool to predict cardiac prognosis of AHF, comparing with conventional statistical model. Abstract Figure. Statistical model

Anatomical factors associated with progression of hallux valgus

BACKGROUND

The purpose of this study was to clarify the incidence rate and the risk factors for the progression of the hallux valgus deformity.

METHODS

Patients who had weight-bearing radiographs of the foot taken twice or more, with a ≥2-year interval, were retrospectively analyzed. Progression of the deformity was defined as an increase in the hallux valgus angle of ≥5° during the follow-up. The association of hallux valgus progression with patient characteristics and radiographic measurements at baseline was determined using univariate and multivariate analyses.

RESULTS

Totally, 268 patients (217 women and 51 men; median age, 64 years) were analyzed. An increase in the hallux valgus angle of ≥5° occurred in 44 (17%) patients in a median follow-up of 49 months. Large hallux valgus angle (odds ratio, 1.07) on the dorsoplantar radiograph at baseline were independent risk factors for the progression of the deformity.

CONCLUSION

Progression of the hallux valgus deformity occurred in one of six patients. Furthermore, large hallux valgus angle was the risk factor for subsequent deformity progression. Patients with large hallux valgus angle should be informed about the possible progression of the deformity.

Effect of Systemic Administration of Granulocyte Colony-Stimulating Factor on a Chronic Partial-Thickness Cartilage Defect in a Rabbit Knee Joint

OBJECTIVE

Cartilage lesions in the knee joint can lead to joint mechanics changes and cause knee pain. Bone marrow stimulation (BMS) promotes cartilage regeneration by perforating the subchondral bone just below the injury and inducing bone marrow cells. This study aimed to investigate whether systemic administration of granulocyte colony-stimulating factor (G-CSF) with BMS improves repair of chronic partial-thickness cartilage defects (PTCDs).

DESIGN

Eighteen 6-month-old New Zealand white rabbits were divided into 3 groups: control (C, n = 6), BMS alone (n = 6), and BMS + G-CSF (n = 6). Partial cartilage defects with 5 mm diameter were created in the trochlear region of both knees; after 4 weeks, the BMS alone and BMS + G-CSF groups underwent BMS; G-CSF (50 µg/kg) or saline was administered subcutaneously for 5 days starting from 3 days before BMS. At 8 and 16 weeks after cartilage defect creation, the area of cartilage defects was macroscopically and histologically evaluated.

RESULTS

International Cartilage Repair Society (ICRS) grades for macroscopic assessment were 0, 0.7, and 0.7 at 8 weeks and 0, 1.2, and 1.3 at 16 weeks in the C, BMS, and BMS + G-CSF groups, respectively. Wakitani scores for histological assessment were 9.8, 8.7, and 8.2 at 8 weeks and 9.5, 9, and 8.2 at 16 weeks in the C, BMS, and BMS + G-CSF groups, respectively. The BMS + G-CSF group showed significantly more repair than the C group, but there was no difference from the BMS group.

CONCLUSIONS

The effect of BMS and G-CSF on chronic PTCDs in mature rabbit knees was limited.

Increase in Achilles Tendon Rupture Surgery in Japan: Results From a Nationwide Health Care Database

Background:

Nationwide epidemiologic studies in Scandinavian countries have shown that the incidence of Achilles tendon ruptures (ATRs) has increased, and the rate of surgical treatment has declined markedly in the past decade. However, there is a lack of national-level data on the trend of ATRs and surgical procedures in other regions.

Purpose:

To clarify the trend in the incidence of ATRs and the proportion of surgery using the nationwide health care database in Japan.

Study Design:

Descriptive epidemiology study.

Methods:

Age- and sex-stratified data on the annual number of ATRs and surgical procedures between 2010 and 2017 were obtained from the Japanese national health care database, which includes almost all inpatient and outpatient medical claims nationwide. The Japanese population data were also obtained from the population census. The change in the annual incidence of ATRs per 100,000 people was assessed using a Poisson regression analysis. The trend in the annual proportion of surgeries relative to the occurrence of tendon ruptures was determined using a linear regression analysis.

Results:

A total of 112,601 ATRs, with men accounting for 67%, were identified over 8 years. Patients aged ≥60 years accounted for 27,106 (24%), while those aged 20 to 39 years and 40 to 59 years accounted for 36,164 (32%) and 49,331 (44%), respectively. The annual incidence of ATR ranged from 12.8/100,000 to 13.9/100,000 (women, 8.2-8.9/100,000; men, 17.2-19.5/100,000), which did not change over the study period (P = .82). Moreover, the annual incidences did not change across sexes and age categories. The annual proportion of surgery increased significantly, from 67% in 2010 to 72% in 2017 (P = .003). The annual proportions increased across sexes and age categories except for women aged 40 to 59 years.

Conclusion:

The incidence of ATR did not change between 2010 and 2017, according to the Japanese nationwide health care database. Furthermore, the proportion of surgical treatment increased during the study period. Overall, 70% of patients underwent surgical treatment. This study suggested that the trend in ATR and surgery differed across regions.

Diagnostic performance of deep learning on 12-leads electrocardiography for recurrence after pulmonary vein isolation in patients with persistent atrial fibrillation

Background

Several patients with persistent atrial fibrillation (per-AF) suffer from recurrence after pulmonary vein isolation (PVI). Various methods to predict the recurrence were tried, but deep learning on 12-leads electrocardiography (ECG) after PVI was not studied.

Purpose

To elucidate diagnostic performance of deep learning on 12-leads ECG after PVI in patients with per-AF

Methods

We enrolled consecutive 109 patients with per-AF who underwent PVI (68.8±10.0 years, 83 males) excluding failure cases. We defined recurrence in 3–12 months after PVI. From the ECG just after PVI, five beats of each lead were sampled separately. Deep learning (convolutional neural network on bitmap ECG image) was performed by transfer learning of Inception-Resnet-V2 model. Gradient weighted class activation color mapping (GradCam) was performed to detect convolutional importance in the lead.

Results

Thirty-six patients showed recurrence in the period. Lead II (accuracy 0.701), aVR (0.690) were the top 2 leads of prediction, which showed larger accuracy than statistical accuracies of Non PV foci = SVC (accuracy = 0.541) and left atrial diameter &gt;50mm (0.596). In lead II, GradCam spotlighted strong convolution of latter half of P wave in recurrent case, and former half of P wave and T wave in no-recurrent case.

Conclusions

Deep learning on ECG was a powerful tool to predict recurrence of per-AF after PVI.

Funding Acknowledgement

Type of funding sources: None. Results of deep learningResults of GradCam

Changes in the Syndesmotic Reduction After Syndesmotic Suture-Button Fixation for Ankle Malleolar Fractures: 1-Year Longitudinal Evaluations Using Computed Tomography

BACKGROUND

Evaluation over time is important in assessing the reduction of the syndesmosis after suture-button fixation for ankle malleolar fractures. The purposes of this study were to evaluate time-dependent change in the syndesmotic reduction immediately after suture-button fixation for ankle malleolus fractures and 1 year after surgery using computed tomography, and to investigate the reliability of the measurement values to evaluate the reduction of syndesmosis.

METHODS

We assessed 28 patients who underwent suture-button fixation for ankle fractures. Syndesmotic reduction was assessed within 2 weeks of the fracture surgery and 1 year after surgery using axial computer tomographic images. Side-to-side differences in the anterior, central, and posterior tibiofibular distances, anteroposterior fibular translation, fibular rotation, and syndesmosis area were measured.

RESULTS

The mean anterior tibiofibular distance and anteroposterior fibular translation were 1.8 mm and 1.5 mm, respectively, after syndesmotic fixation. They decreased to 1.2 mm and 0.6 mm, respectively, at 1 year after surgery (P = .03 and P = .01, respectively). The other measurement values did not change over time. The minimum detectable change in the distance of measurements was 1 mm or less.

CONCLUSION

The anterior tibiofibular distance and anteroposterior fibular translation had decreased 1 year after fixation in ankle malleolar fractures with syndesmotic suture button. Even if the fibula is posteriorly malreduced by the time computed tomography is performed immediately after surgery, the fibula may return to a good position 1 year after surgery.

LEVEL OF EVIDENCE

Level IV, case series.

E_{8} Spectra of Quasi-One-Dimensional Antiferromagnet BaCo_{2}V_{2}O_{8} under Transverse Field

We report ^{51}V NMR and inelastic neutron scattering (INS) measurements on a quasi-1D antiferromagnet BaCo_{2}V_{2}O_{8} under transverse field along the [010] direction. The scaling behavior of the spin-lattice relaxation rate above the Néel temperatures unveils a 1D quantum critical point (QCP) at H_{c}^{1D}≈4.7  T, which is masked by the 3D magnetic order. With the aid of accurate analytical analysis and numerical calculations, we show that the zone center INS spectrum at H_{c}^{1D} is precisely described by the pattern of the 1D quantum Ising model in a magnetic field, a class of universality described in terms of the exceptional E_{8} Lie algebra. These excitations are nondiffusive over a certain field range when the system is away from the 1D QCP. Our results provide an unambiguous experimental realization of the massive E_{8} phase in the compound, and open a new experimental route for exploring the dynamics of quantum integrable systems as well as physics beyond integrability.

Scleraxis upregulated by transforming growth factor-β1 signaling inhibits tension-induced osteoblast differentiation of priodontal ligament cells via ephrin A2

During tooth movement in orthodontic treatment, bone formation and resorption occur on the tension and compression sides of the alveolar bone, respectively. Although the bone formation activity increases in the periodontal ligament (PDL) on the tension side, the PDL itself is not ossified and maintains its homeostasis, indicating that there are negative regulators of bone formation in the PDL. Our previous report suggested that scleraxis (Scx) has an inhibitory effect on ossification of the PDL on the tension side through the suppression of calcified extracellular matrix formation. However, the molecular biological mechanisms of Scx-modulated inhibition of ossification in the tensioned PDL are not fully understood. The aim of the present study is to clarify the inhibitory role of Scx in osteoblast differentiation of PDL cells and its underlying mechanism. Our in vivo experiment using a mouse experimental tooth movement model showed that Scx expression was increased during early response of the PDL to tensile force. Scx knockdown upregulated expression of alkaline phosphatase, an early osteoblast differentiation marker, in the tensile force-loaded PDL cells in vitro. Transforming growth factor (TGF)-β1-Smad3 signaling in the PDL was activated by tensile force and inhibitors of TGF-β receptor and Smad3 suppressed the tensile force-induced Scx expression in PDL cells. Tensile force induced ephrin A2 (Efna2) expression in the PDL and Efna2 knockdown upregulated alkaline phosphatase expression in PDL cells under tensile force loading. Scx knockdown eliminated the tensile force-induced Efna2 expression in PDL cells. These findings suggest that the TGF-β1-Scx-Efna2 axis is a novel molecular mechanism that negatively regulates the tensile force-induced osteoblast differentiation of PDL cells.

Influence of rotational speed on torque/force generation and shaping ability during root canal instrumentation of extracted teeth with continuous rotation and optimum torque reverse motion

AIM

To evaluate how different rotational speeds affect the torque/force generation and shaping ability of rotary root canal instrumentation using JIZAI (MANI, Utsunomiya, Japan) nickel-titanium instruments in continuous rotation and optimum torque reverse (OTR) motion.

METHODOLOGY

Mesial root canals of extracted mandibular molars were instrumented up to size 25, 0.04 taper using JIZAI instruments, and anatomically matched canals were selected based on geometric features of the canal [canal volume (mm³ ), surface area (mm² ), length, 15°-20° curvature and radius of curvature (4-8 mm)] after micro-computed tomographic scanning. An automated root canal instrumentation and torque/force analysing device was programmed to permit a simulated pecking motion (2 s downward and 1 s upward at 50 mm min^-1 ). The selected canals were prepared with size 25, 0.06 taper JIZAI instruments using continuous rotation or OTR motion and further subdivided according to the rotational speed (300 or 500 rpm, n = 10 each). Real-time clockwise/counterclockwise torque and downward/upward force were recorded using a custom-made torque/force analysing device. Then, the registered pre- and post-operative micro-computed tomographic datasets were examined to evaluate the canal volume changes and centring ratios at 1, 3, 5 and 7 mm from the apical foramen. Data were analysed using two-way analysis of variance or the Kruskal-Wallis test and Mann-Whitney U test with Bonferroni correction (α = 5%).

RESULTS

Maximum upward force and clockwise torque were significantly smaller in 500 rpm groups than in 300 rpm groups (P < .05); however, no significant difference was found between continuous rotation and OTR motion (P > .05). OTR motion developed higher maximum counterclockwise torque than continuous rotation (P < .05). Maximum downward force, canal volume changes and centring ratios were not significantly different among all groups (P > .05). There was no file fracture in any of the groups.

CONCLUSIONS

Under laboratory conditions using JIZAI instruments, a rotational speed of 500 rpm generated significantly lower maximum screw-in forces and torque values than rotational speed of 300 rpm. Continuous rotation and OTR motion performed similarly in shaping the canals.

In vitro evidence of propagation of superoxide dismutase-1 protein aggregation in canine degenerative myelopathy

Canine degenerative myelopathy (DM) is a progressive and fatal neurodegenerative disorder that has been linked to mutations in the superoxide dismutase 1 (SOD1) gene. The accumulation of misfolded protein aggregates in spinal neurons and astrocytes is implicated as an important pathological process in DM; however, the mechanism of protein aggregate formation is largely unknown. In human neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), cell-to-cell propagation of disease-relevant proteins has been demonstrated. Therefore, in this study, propagation of aggregation-forming property of mutant SOD1 protein in DM in vitro was investigated. This study demonstrated that aggregates composed of canine wild type SOD1 protein were increased by co-transfection with canine mutant SOD1 (E40K SOD1), indicating intracellular propagation of SOD1 aggregates. Further, aggregated recombinant SOD1 proteins were released from the cells, taken up by other cells, and induced further aggregate formation of normally folded SOD1 proteins. These results suggest intercellular propagation of SOD1 aggregates. The hypothesis of cell-to-cell propagation of SOD1 aggregates proposed in this study may underly the progressive nature of DM pathology.

Randomized comparative study of suspension femoral fixation device in graft position maintenance in anterior cruciate ligament reconstruction: EndoButton CL vs TightRope RT

Background

In double-bundle anterior cruciate ligament reconstruction (ACLR), fixed-loop and adjustable-loop cortical suspensory devices are commonly used to fix the soft graft on the femoral side. However, few studies have compared in vivo elongation of the two devices. The purpose of this study was to determine whether EndoButton CL (EB) and TightRope RT (TR), the suspensory fixation devices used in ACLR, maintained their length in vivo from the time of surgery through the postoperative period in a randomized controlled trial.

Methods

This study prospectively incorporated 30 patients undergoing initial ACLR at a single center. Participants were divided into two groups using a stratified randomization method with age and sex as assignment adjustment factors. EB or TR was used for fixation of the soft graft on the femoral side. The primary endpoint was to compare the elongation distance of the suspensory device. MRIs were taken within seven days after ACLR and 3,6,12 months postoperatively and measured by a radiologist in a blinded fashion. Secondary endpoints included the side-to-side difference in anterior translation, one leg hop test (HOP index), Lachman test, lateral pivot shift test, and Lysholm score one year postoperatively.

Results

Twenty-eight patients (EB, n = 13; TR, n = 15) were followed for one year. There was no significant difference between EB and TR groups in elongation from the immediate postoperative period to 3, 6, 12 months after surgery. However, the non-inferiority of TR to EB (non-inferiority margin: 1.5 mm) was not proved by the difference in measured elongation between the two groups (TR – EB, lower 95% CI. AM: 1.80 mm; PL: 1.86 mm) at 6 months. There was no significant difference in anterior translation, HOP index, Lachman test, lateral pivot shift test, or Lysholm score.

Conclusion

EB and TR had similar graft retaining ability in vivo for 12 months, but the non-inferiority of TR against EB was not verified statistically.

A case of Infective Native (Abdominal) Aortic Aneurysm Caused by Streptococcus Agalactiae: An Updated Literature Review Based on New Nomenclature

The management of abdominal aortic aneurysms (AAA) has evolved significantly with the advent of endovascular strategies. Thus, there has been a decline in the number of open AAA repairs once an endovascular option is available. There have also been reports of successful endovascular management of infective native aortic aneurysms (INAA)¹, previously called mycotic aneurysms². The rarity of this condition makes its management a challenging one as there are no standard guidelines. The European Society of Vascular Surgery has suggested that the nomenclature be changed from mycotic aneurysms as this can be misleading to standardise reporting¹. The authors' present a case of a 67-year old male who presented during the peak of the Corona Virus pandemic with constitutional gastrointestinal symptoms. He was subsequently diagnosed with an INAA and successfully managed with open Neo-Aorto Iliac System reconstruction with a homograft³. The report highlights various strategies used in the surgical approach and their benefits in the management of INAA. Furthermore, a literature review of Streptococcus (Streptococcus agalactiae) species as a rare cause of INAA and how these cases were managed are also highlighted.

Ten-m/Odz3 regulates migration and differentiation of chondrogenic ATDC5 cells via RhoA-mediated actin reorganization

Tenascin-like molecule major (Ten-m)/odd Oz (Odz), a type II transmembrane molecule, is well known to modulate neural development. We have reported that Ten-m/Odz3 is expressed in cartilaginous tissues and cells. Actin cytoskeleton and its regulator ras homolog gene family member A (RhoA) are closely associated with chondrogenesis. The present study aimed to evaluate the function and molecular mechanism of Ten-m/Odz3 during chondrogenesis, focusing on RhoA and the actin cytoskeleton. Ten-m/Odz3 was expressed in precartilaginous condensing mesenchyme in mouse limb buds. Ten-m/Odz3 knockdown in ATDC5 induced actin cytoskeleton reorganization and change of cell shape through modulation of RhoA activity and FGF2 expression. Ten-m/Odz3 knockdown suppressed ATDC5 migration and expression of genes associated with chondrogenesis, such as Sox9 and type II collagen, via RhoA. On the other hand, Ten-m/Odz3 knockdown inhibited proliferation of ATDC5 in a RhoA-independent manner. These findings suggest that Ten-m/Odz3 plays an important role in early chondrogenesis regulating RhoA-mediated actin reorganization.

Connective tissue growth factor promotes chemotaxis of preosteoblasts through integrin α5 and Ras during tensile force-induced intramembranous osteogenesis

In vertebrates, new bone formation via intramembranous osteogenesis is a critical biological event for development, remodeling, and fracture healing of bones. Chemotaxis of osteoblast lineage cells is an essential cellular process in new bone formation. Connective tissue growth factor (CTGF) is known to exert chemotactic properties on various cells; however, details of CTGF function in the chemotaxis of osteoblast lineage cells and underlying molecular biological mechanisms have not been clarified. The aim of the present study was to evaluate the chemotactic properties of CTGF and its underlying mechanisms during active bone formation through intramembranous osteogenesis. In our mouse tensile force-induced bone formation model, preosteoblasts were aggregated at the osteogenic front of calvarial bones. CTGF was expressed at the osteogenic front, and functional inhibition of CTGF using a neutralizing antibody suppressed the aggregation of preosteoblasts. In vitro experiments using μ-slide chemotaxis chambers showed that a gradient of CTGF induced chemotaxis of preosteoblastic MC3T3-E1 cells, while a neutralizing integrin α5 antibody and a Ras inhibitor inhibited the CTGF-induced chemotaxis of MC3T3-E1 cells. These findings suggest that the CTGF-integrin α5-Ras axis is an essential molecular mechanism to promote chemotaxis of preosteoblasts during new bone formation through intramembranous osteogenesis.

A cylindrical SiC heater for an externally heated diamond anvil cell to 1500 K

Semiconductor-based heaters for diamond anvil cells (DACs) have advantages over metal wire heaters in terms of repeated use and the ability to reach higher temperatures. We introduce a cylindrical SiC heater for an externally heated DAC (EHDAC) that works satisfactorily at temperatures up to 1500 K and pressures around 90 GPa. The heater is reusable and inexpensive, and only slight modifications to the DAC are required to fit the heater. Experiments on melting of NaCl and gold are conducted at ambient pressure to test the temperature accuracy of the EHDAC system, and resistance measurements on iodine at high pressures and temperatures are performed to assess the heater assembly. These test runs show that a uniform and accurate temperature can be maintained by the EHDAC assembly, which has potential applications to a variety of transport property measurements.

In vivo kinematics of cruciate-retaining total knee arthroplasty after a change of polyethylene insert configuration

Background

To investigate in vivo kinematics of total knee arthroplasty (TKA) with the introduction of a mildly constrained (MC) type of polyethylene (PE). We compared the knee kinematics with a reported pattern after surgery using the same component with a conventionally constrained (CC) type of PE.

Methods

Finite element analysis (FEA) was performed to examine different peak stress distribution of both types of PE. For in vivo study, patients who underwent cruciate-retaining TKA using a total knee system with MC-PE were included. Fluoroscopic surveillance was used to measure the weight-bearing deep knee bend (squatting) using a two-dimensional/three-dimensional (2-D/3-D) registration technique.

Results

FEA analysis revealed the edge loading of the femoral component on PE in CC but not in MC. During the study period, 42 patients underwent TKA with MC-PE. Among them, 13 agreed to participate in the present study. In vivo kinematics analysis found that starting from an average external rotation of femur being 7.1° at 0° of flexion, the rotation slightly decreased to 6.8° at 10° of flexion, then increased with increasing knee flexion until it reached 10.8° at 80° of flexion, and finally decreased to 9.8° at 100° of knee flexion. The results indicate a modest medial pivot pattern. Although the overall pattern was similar for both MC-PE and CC-PE, a slight difference was observed. MC-PE showed a slight internal rotation of 0.3° from 0 to 10° of knee flexion, whereas CC-PE showed a gradual increase of external rotation in this range.

Conclusions

Change of configuration from CC to MC did not substantially affect in vivo kinematics of knees after TKA. Considering the theoretical wider range of allowance of rotation, MC-PE is easier for knee surgeons to use.

Prediction for cardiac prognosis in patients with congestive heart failure by machine learning on dual-isotope myocardial semiconductor SPECT

Background

Dual-isotope (low doze 201TlCl and 123I-β-methyl-P-iodophenyl-pentadecanoic acid (BMIPP)) single photon emission computed tomography (SPECT) is utilized to estimate myocardial damage in patients with congestive heart failure (CHF). However, predictive model construction on the SPECT for cardiac death by machine learning was not studied.

Purpose

To elucidate predictive value of machine learning model on dual-isotope SPECT for CHF.

Methods

We enrolled consecutive 310 patients who admitted with CHF (77.1±3.1 years, 164 males). After initial treatment, they underwent electrocardiography gated SPECT and observed in median 507 days [IQR: 165, 1032]. Multivariate Cox regression analysis for cardiac death was performed, and predictive model was constructed by ROC curve analysis and machine learning (Random Forest and Deep Learning). The accuracies (= [True positive + True negative] / Total) of the prediction models were compared with ROC curve model.

Results

Thirty-six patients fell into cardiac death. Cox analysis showed Age, left ventricular ejection fraction (LVEF), summed rest score (SRS) of BMIPP, and mismatch score were significant predictors (Hazard ratio: 1.068, 0.970, 1.032, 1.092, P value: &lt;0.001, 0.014, 0.002, &lt;0.001, respectively). ROC curve analysis of them revealed the accuracy of the cut-off value was 0.479–0.773. Conversely, machine learning model demonstrated higher accuracy for cardiac death (Random Forest: 0.895, Deep Learning: 0.935). The top 4 feature importance of the random forest were LVEF (0.299), SRS BMIPP (0.263), Age (0.262), and mismatch score (0.160).

Conclusion

Machine learning model on SPECT was superior to conventional statistic model for predicting cardiac death in patients with CHF.

Funding Acknowledgement

Type of funding source: None

The comparison of the chronic-phase vascular healing between bioabsorbable and durable polymer drug eluting stent by using optical coherence tomography

Background

Bioabsorbable polymer drug eluting stents (BP-DESs) were designed to reduce a vascular inflammatory reaction compared to durable polymer drug eluting stents (DP-DESs). However, few studies have compared vascular responses to BP-DESs and DP-DESs.

Methods

We enrolled 88 consecutive patients with single culprit coronary artery lesions (31 lesions with acute coronary syndrome) undergoing a single stent-implantation. BP-DESs and DP-DESs were implanted in 50 (57%) and 38 patients (43%), respectively. All lesions underwent optical coherence tomography examination at chronic phase and intrastent OCT findings at the follow-up were evaluated in every 1-mm cross-sections (CSs).

Results

A total of 1887 CSs (BP-DES: 1096, DP-DES: 791) were analyzed. The median period of follow-up OCT was 293 (250–374) days. There were no differences in the patient, lesion, and initial clinical presentation of acute coronary syndrome (ACS). BP-DESs had significantly higher percent neointimal hyperplasia area, defined as neointimal hyperplasia area divided by stent area x 100 (18.4±9.0% vs. 16.1±9.9%, p&lt;0.001), fewer malapposed struts (1.7% vs. 3.9%, p=0.005), fewer uncovered struts (3.6% vs. 5.8%, p=0.02) but higher frequency of superficial low intensity neointima (LIN) (7.7% vs. 3.4%, p&lt;0.001). Multivariate logistic analysis showed that BP-DES (OR: 2.5, 95% CI: 1.49–4.08, p&lt;0.001) and the initial clinical presentation of ACS (OR: 2.31, 95% CI: 1.47–3.62, p&lt;0.001) are independent predictive factors for LIN.

Conclusion

BP-DESs showed homogenous neointimal growth and complete stent coverage quantitatively. Meanwhile, the significant relationships of BP-DES with LIN may suggest that the neointimal quality remains immature in BP-DESs in this period.

Funding Acknowledgement

Type of funding source: None