Partial Stent-in-Stent Method with an Uncovered Self-Expandable Metallic Stent for Unresectable Malignant Hilar Bile Duct Obstruction

(1) Background: There is controversy regarding stent placement for unresectable malignant hilar biliary obstruction (UMHBO). We mainly use the partial stent-in-stent (PSIS) method with an uncovered self-expandable metallic stent (UCSEMS) based on the drainage area and patency period. In this study, we investigated the usefulness and safety of the PSIS method. (2) Methods: In total, 59 patients who underwent the PSIS method for UMHBO at our hospital were included in the study. The technical success rate, clinical success rate, time to recurrent biliary obstruction (TRBO) and overall survival (OS) from the first placement, factors affecting TRBO and OS, and early complications within 30 days after the procedure were evaluated retrospectively. (3) Results: The technical and clinical success rates were 100% and 96.6%, respectively, with a TRBO of 121 days [95% confidence interval: 82-231] and an OS of 194 days [95% confidence interval: 113-305] after the first placement. Early complications occurred in nine patients (15.3%), including five cases of cholangitis, three cases of pancreatitis, and one case of cholecystitis. (4) Conclusions: The PSIS method for UMHBO is safe and useful with high technical and clinical success rates.

Anaerobic threshold using sweat lactate sensor under hypoxia

We aimed to investigate the reliability and validity of sweat lactate threshold (sLT) measurement based on the real-time monitoring of the transition in sweat lactate levels (sLA) under hypoxic exercise. In this cross-sectional study, 20 healthy participants who underwent exercise tests using respiratory gas analysis under hypoxia (fraction of inspired oxygen [FiO2], 15.4 ± 0.8%) in addition to normoxia (FiO2, 20.9%) were included; we simultaneously monitored sLA transition using a wearable lactate sensor. The initial significant elevation in sLA over the baseline was defined as sLT. Under hypoxia, real-time dynamic changes in sLA were successfully visualized, including a rapid, continual rise until volitionary exhaustion and a progressive reduction in the recovery phase. High intra- and inter-evaluator reliability was demonstrated for sLT's repeat determinations (0.782 [0.607-0.898] and 0.933 [0.841-0.973]) as intraclass correlation coefficients [95% confidence interval]. sLT correlated with ventilatory threshold (VT) (r = 0.70, p < 0.01). A strong agreement was found in the Bland-Altman plot (mean difference/mean average time: - 15.5/550.8 s) under hypoxia. Our wearable device enabled continuous and real-time lactate assessment in sweat under hypoxic conditions in healthy participants with high reliability and validity, providing additional information to detect anaerobic thresholds in hypoxic conditions.

Impacts of an age-related hearing loss allele of cadherin 23 on severity of hearing loss in ICR and NOD/Shi mice

The age-related hearing loss allele (Cdh23ahl) of the cadherin 23 gene leads to a more severe hearing loss phenotype through additive effects with risk alleles for hearing loss. In this study, we genome edited the Cdh23ahl allele to the wild-type Cdh23+ allele in outbred ICR mice and inbred NOD/Shi mice established from ICR mice and investigated their effects on hearing phenotypes. Several hearing tests confirmed that ICR mice developed early onset high-frequency hearing loss and exhibited individual differences in hearing loss onset times. Severe loss of cochlear hair cells was also detected in the high-frequency areas in ICR mice. These phenotypes were rescued by genome editing the Cdh23ahl allele to Cdh23+, suggesting that abnormal hearing phenotypes develop because of the interaction of the Cdh23ahl and risk alleles in the genetic background of ICR mice. NOD/Shi mice developed more severe hearing loss and hair cell degeneration than ICR mice. Hearing loss was detected at 1 month old. Hair cell loss, including degeneration of cell bodies and stereocilia, was observed in all regions of the cochlea in NOD/Shi mice. Although these phenotypes were partially rescued by genome editing to the Cdh23+ allele, the phenotypes associated with high-frequency hearing were mostly unrecovered in NOD/Shi mice. These results strongly suggest that the genetic background of NOD/Shi mice contain a potential risk allele for the acceleration of early onset high-frequency hearing loss.

Prognostic Implications and Efficacy of Catheter Ablation by Atrial Fibrillation Type

Background Catheter ablation (CA) for atrial fibrillation (AF) is preferred for paroxysmal AF (PAF) but selectively performed in patients with persistent AF (PersAF). This study aimed to investigate the prognostic differences and consequences of CA based on the AF type. Methods and Results Data from a multicenter AF cohort study were analyzed, categorizing patients as PAF or PersAF according to AF duration (≤7 or >7 days, respectively). A composite of all-cause death, heart failure hospitalization, stroke, and bleeding events during 2-year follow-up and changes in the Atrial Fibrillation Effect on Quality-of-life score were compared. Additionally, propensity score matching was performed to compare clinical outcomes of patients with and without CA in both AF types. Among 2788 patients, 51.6% and 48.4% had PAF and PersAF, respectively. Patients with PersAF had a higher incidence of the composite outcome (12.8% versus 7.2%; P<0.001) and smaller improvements in Atrial Fibrillation Effect on Quality-of-life scores than those with PAF. After adjusting for baseline characteristics, PersAF was an independent predictor of adverse outcomes (adjusted hazard ratio, 1.35 [95% CI, 1.30-1.78], P=0.031) and was associated with poor improvements in Atrial Fibrillation Effect on Quality-of-life scores. Propensity score matching analysis showed that the CA group had significantly fewer adverse events than the medication group among patients with PAF (odds ratio, 0.31 [95% CI, 0.18-0.68]; P=0.002). Patients with PersAF showed a similar but nonsignificant trend. Conclusions PersAF is a risk factor for worse clinical outcomes, including patients' health status. CA is associated with fewer adverse events, although careful consideration is required based on the AF type.

Real-Time Estimation of Anaerobic Threshold during Exercise Using Electrocardiogram in Heart Failure Patients

Exercise therapy at the aerobic level is highly recommended to improve clinical outcomes in patients with heart failure, in which cardiopulmonary exercise testing (CPX) is required to determine anaerobic thresholds (ATs) but is not available everywhere. This study aimed to validate a method to estimate the AT using heart rate variability (HRV) analysis from electrocardiography data in patients with heart failure. Between 2014 and 2019, 67 patients with symptomatic heart failure underwent CPXs in a single university hospital. During the CPX, RR intervals was measured continuously and the HRV threshold (HRVT), defined as the inflection point of <5 ms2 of a high-frequency component (HFC) using the power spectrum analysis, was determined. Patients were divided into two groups according to the mean HFC at rest (high-HFC group, n = 34 and low-HFC group, n = 33). The high-HFC group showed good correlation between the VO2 at AT and HRVT (r = 0.63, p < 0.001) and strong agreement (mean difference, -0.38 mL/kg, p = 0.571). The low-HFC group also showed modest correlation (r = 0.41, p = 0.017) but poor agreement (mean differences, 3.75 mL/kg, p < 0.001). In conclusion, the HRVT obtained from electrocardiography may be a useful indicator for estimating AT in patients with heart failure.

Delineation of conduction gaps of linear lesions during atrial fibrillation ablation using ultra-high-density mapping

AIMS

Linear lesions are routinely created by radiofrequency catheter ablation. Unwanted electrical conduction gaps can be produced and are often difficult to ablate. This study aimed to clarify the characteristics of conduction gaps during atrial fibrillation ablation by analysing bidirectional activation maps using a high-density mapping system (RHYTHMIA).

METHODS AND RESULTS

This retrospective study included 31 patients who had conduction gaps along pulmonary vein (PV) isolation or box ablation lesions. Activation maps were sequentially created during pacing from the coronary sinus and PV to reveal the earliest activation site, defined by the entrance and exit. The locations, length between the entrance and exit (gap length), and direction were analysed. Thirty-four bidirectional activation maps were drawn: 21 were box isolation lesions (box group), and 13 were PV isolation lesions (PVI group). Among the box group, nine conduction gaps were present in the roof region and 12 in the bottom region, while nine in right PV and four in left PV among the PVI group. Gap lengths in the roof region were longer than those in the bottom region (26.8 ± 11.8 vs. 14.5 ± 9.8 mm; P = 0.022), while those in right PV tended to longer than those in left PV (28.0 ± 15.3 vs. 16.8 ± 8.0 mm, P = 0.201).

CONCLUSION

The entrances and exits of electrical conduction gaps were separated, especially in the roof region, indicating that epicardial conduction might contribute to gap formation. Identifying the bidirectional conduction gap might indicate the location and direction of epicardial conduction.

Pancreatic Juice Cytology Evaluations Using Synthetic Secretin and Serial Pancreatic Juice Aspiration Cytological Examination for the Diagnosis of Pancreatic Ductal Adenocarcinoma

Pathological examination by endoscopic ultrasound-fine needle aspiration is not possible in approximately 10% of pancreatic tumor cases. Pancreatic juice cytology (PJC) is considered an alternative diagnostic method. However, its diagnostic capability is insufficient, and PJC has been repeatedly redevised. Serial pancreatic juice aspiration cytological examination (SPACE) and secretin-loaded PJC (S-PJC) have been recently introduced as alternative diagnostic methods. This study aimed to determine the diagnostic capacity and safety of SPACE and S-PJC using a propensity score-matched analysis. The sensitivity, specificity, and accuracy were 75.0%, 100%, and 92.3% for S-PJC, respectively, and 71.4%, 100%, and 92.3% for SPACE, respectively, meaning that there was no significant difference between the groups. Four patients (15.4%) each in the S-PJC and SPACE groups experienced complications, including postendoscopic retrograde cholangiopancreatography, pancreatitis, and cholangitis. Overall, there was no difference in efficacy and safety between the SPACE and S-PJC groups.

Real-time analysis of heart rate variability during aerobic exercise in patients with cardiovascular disease

Background

Exercise therapy for cardiovascular disease (CVD) is mainly evaluated based on the heart rate (HR) or Borg scale. However, these indices can be unreliable depending on the patient’s medication or their subjective decisions; thus, alternative methods are required for easier and safer implementation of aerobic exercise. Here, we examined whether real-time analysis of HR variability (HRV) can help maintain exercise intensity at the ventilatory threshold (VT) during exercise.

Methods

Twenty-eight patients with CVD treated at Keio University Hospital between August 2018 and March 2020 were enrolled. Initially, oxygen uptake (VO₂) and HR at the VT were determined using the cardiopulmonary exercise test. Patients then performed aerobic exercise on a stationary bicycle for 30 min while a parameter of HRV, the high-frequency (HF) component, was monitored in real time using an electrocardiograph. The work rate during exercise was adjusted every 2 min to maintain the HF range between 5 and 10. The VO₂ and HR values, recorded every 2 min during exercise, were compared with those at VT. The Bland–Altman method was used to confirm similarity.

Results

VO₂ and HR during exercise were closely correlated with those at VT (e.g., 19 min after exercise initiation; VO₂: r = 0.647, HR: r = 0.534). The Bland–Altman plot revealed no bias between the mean values (e.g., 19 min; VO₂: −0.22 mL/kg/min; HR: −0.07/min).

Conclusion

Real-time HRV analysis with electrocardiograph alone during exercise can provide continuous and non-invasive exercise intensity measurements at VT, promoting safer and effective exercise strategies.

Characteristics and health-status outcomes in patients with atrial fibrillation detected via health screening

BACKGROUND

Early detection of atrial fibrillation (AF) is important. Japan has a universal screening system, and regular health screening (HS) is available to support AF detection without a hospital visit. However, health-related outcomes and other characteristics of HS-detected and conventionally diagnosed AF remain unknown.

HYPOTHESIS

That the characteristics and health-related outcomes of patients with HS-detected AF may differ from those of patients whose AF was detected by other procedures.

METHODS

In total, 3318 consecutive newly referred AF cases were enrolled; demographic characteristics and health-related and clinical outcomes were compared between two groups created based on the mode of AF detection (the HS and non-HS groups). Health-related outcomes were assessed using the AF Effect on QualiTy-of-life (AFEQT) questionnaire at baseline and after 1 year of follow-up.

RESULTS

AF was detected by HS in 25.0% of patients; these patients had lower CHADS₂ scores (1.01 vs. 1.50, p < .001), higher prevalence of persistent AF (odds ratio, 95% confidence interval; 2.21, 1.88-2.60) and asymptomatic presentation (3.19, 2.71-3.76), and better baseline QoL scores (83.6 vs. 75.0; p < .001). Catheter ablation was more frequently performed in the HS group at follow-up (44.4% vs. 34.1%; p < .001). At 1-year follow-up, the AFEQT scores of the HS group were significantly better in most subdomains.

CONCLUSIONS

In the Japanese registry, AF was detected via HS in 25% of patients referred to specialty centers for management. Notably, the overall health status of patients with HS-detected AF improved after medical interventions, including catheter ablations.

Advantage of POLARx over ARCTIC FRONT ADVANCE PRO during pulmonary vein isolation for paroxysmal atrial fibrillation

Introduction

The electrical pulmonary vein (PV) isolation has been established as a curative therapy for paroxysmal atrial fibrillation (AF). Arctic Front™cryoballoon has been used worldwide for AF cryoablation. Recently, a new cryoballoon, POLARxTM CRYOABLATION system have been introduced, of which material of the balloon is softer and the N2O gas flow rate is higher.

Purpose

The aim was to investigate the procedural parameter and efficacy of POLARx comparing with Arctic Front.

Methods

This retrospective single center study included 101 consecutive patients who underwent paroxysmal AF ablation using cryoballoon at Keio University hospital from April 2021 to March 2022. The procedural data including the cryoballoon temperature and the number and duration of cryoablation were compared between POLARx (POLARx group) and ARCTIC FRONT ADVANCE PRO (AFA group). After the cryoablation, we added the radiofrequency application in order to maximize the isolated area when the voltage was remained inside PV (Figure 1). The necessities of the additional radiofrequency applications were also compared.

Results

In the present study, 64 patients in AFA group and 37 patients in POLARx group were analyzed. POLARx group included younger population and less females (62.8±9.9 vs 67.5±9.4 year of age, P=0.02; 13.5 vs 32.8%, P=0.04). There was no significant difference in comorbidities and examination data such as left atrium diameter or brain natriuretic peptide level. The minimal cryoballoon temperatures reached in POLARx group were lower than AFA group (−59.3±6.2 vs −47.7±7.5°C, P&lt;0.01). No difference was found in the total number and duration of cryoablation and the time to isolate PV (6.1±2.1 vs 5.9±1.6, P=0.69; 790.2±256.1 vs 776.1±235.0 sec, P=0.69; 41.8±21.3 vs 47.1±29.6 sec, P=0.44, respectively). With regard to individual PVs, the total number and duration were tended to be larger at right superior PV in POLARx group (1.9±1.1 vs 1.4±0.7, P=0.01; 231.8±123.8 vs 193.2±83.0 sec, P=0.07), while there was no significant difference at the other PVs. The rate of successful PV isolation by a single cryo-application was not different between AFA and POLARx group (54.3 vs 61.4%, P=0.17). The additional radiofrequency applications were more frequent in AFA group (14.8 vs. 4.9%, P=0.003). There was a significant difference at right inferior PV (32.8 vs 8.1%, P=0.01), while not at left superior PV, left inferior PV and right superior PV (9.4 vs 2.9%, P=0.42; 9.4 vs 5.7%, P=0.71; 7.8 vs 2.7%, P=0.41). Phrenic nerve injury was occurred 1 case in both group and esophageal ulcer was occurred in 1 case in AFA group. No other complication including cardiac tamponade was occurred.

Conclusion

The total number and duration of cryoablation were not significantly different between AFA and POLARx group, except for right superior PV. There was an advantage in largely isolating right inferior PV in POLARx group comparing with AFA group.

Funding Acknowledgement

Type of funding sources: None.

Two Loci Contribute to Age-Related Hearing Loss Resistance in the Japanese Wild-Derived Inbred MSM/Ms Mice

An MSM/Ms strain was established using Japanese wild mice, which exhibit resistance to several phenotypes associated with aging, such as obesity, inflammation, and tumorigenesis, compared to common inbred mouse strains. MSM/Ms strain is resistant to age-related hearing loss, and their auditory abilities are sustained for long durations. The age-related hearing loss 3 (ahl3) locus contributes to age-related hearing in MSM/Ms strain. We generated ahl3 congenic strains by transferring a genomic region on chromosome 17 from MSM/Ms mice into C57BL/6J mice. Although C57BL/6J mice develop age-related hearing loss because of the ahl allele of the cadherin 23 gene, the development of middle- to high-frequency hearing loss was significantly delayed in an ahl3 congenic strain. Moreover, the novel age-related hearing loss 10 (ahl10) locus associated with age-related hearing resistance in MSM/Ms strain was mapped to chromosome 12. Although the resistance effects in ahl10 congenic strain were slightly weaker than those in ahl3 congenic strain, slow progression of age-related hearing loss was confirmed in ahl10 congenic strain despite harboring the ahl allele of cadherin 23. These results suggest that causative genes and polymorphisms of the ahl3 and ahl10 loci are important targets for the prevention and treatment of age-related hearing loss.

Gli1+-PDL Cells Contribute to Alveolar Bone Homeostasis and Regeneration

The periodontal ligament (PDL) contains mesenchymal stem cells (MSCs) that can differentiate into osteoblasts, cementoblasts, and fibroblasts. Nevertheless, the distribution and characteristics of these cells remain uncertain. Gli1, an essential hedgehog signaling transcription factor, functions in undifferentiated cells during embryogenesis. Therefore, in the present study, the differentiation ability of Gli1⁺ cells was examined using Gli1-CreERT2/ROSA26-loxP-stop-loxP-tdTomato (iGli1/Tomato) mice. In 4-wk-old iGli1/Tomato mice, Gli1/Tomato⁺ cells were only slightly detected in the PDL, around endomucin-expressing blood vessels. These cells had proliferated over time, localizing in the PDL as well as on the bone and cementum surfaces at day 28. However, in 8-wk-old iGli1/Tomato mice, Gli1/Tomato⁺ cells were quiescent, as most cells were not immunoreactive for Ki-67. These cells in 8-wk-old mice exhibited high colony-forming unit fibroblast activity and were capable of osteogenic, chondrogenic, and adipogenic differentiation in vitro. In addition, after transplantation of teeth of iGli1/Tomato mice into the hypodermis of wild-type mice, Tomato fluorescence indicating the progeny of Gli1⁺ cells was detected in the osteoblasts and osteocytes of the regenerated bone. These results demonstrate that Gli1⁺ cells in the PDL were MSCs and could contribute to the alveolar bone regeneration.

3CL Protease Inhibitors with an Electrophilic Arylketone Moiety as Anti-SARS-CoV-2 Agents

The novel coronavirus, SARS-CoV-2, has been identified as the causative agent for the current coronavirus disease (COVID-19) pandemic. 3CL protease (3CLpro) plays a pivotal role in the processing of viral polyproteins. We report peptidomimetic compounds with a unique benzothiazolyl ketone as a warhead group, which display potent activity against SARS-CoV-2 3CLpro. The most potent inhibitor YH-53 can strongly block the SARS-CoV-2 replication. X-ray structural analysis revealed that YH-53 establishes multiple hydrogen bond interactions with backbone amino acids and a covalent bond with the active site of 3CLpro. Further results from computational and experimental studies, including an in vitro absorption, distribution, metabolism, and excretion profile, in vivo pharmacokinetics, and metabolic analysis of YH-53 suggest that it has a high potential as a lead candidate to compete with COVID-19.

Change in the local impedance and electrograms recorded by a micro-electrode tip catheter during initial atrial fibrillation ablation

BACKGROUND

A novel measurement of the local impedance (LI) and electrograms recorded from micro-electrodes on catheter tip has been developed. However, the data during pulmonary vein (PV) ablation is not sufficient. We aimed to investigate the utility of this measurement during initial atrial fibrillation (AF) ablation.

METHODS

We investigated 111 representative radiofrequency applications in 7 AF patients without a history of prior ablation (6 males, age 68 [65-72] years, 2 persistent AF). The ablation strategy was PV isolation for paroxysmal AF and single ring box isolation for persistent AF, using MiFi catheter. The correlation of the generator impedance (GI) drop and LI drop after radiofrequency applications and the predictive value of the initial LI elevation before radiofrequency applications for LI drop were analyzed. Also, the LI and GI drop were investigated according to the location of RF applications.

RESULTS

The LI drop was higher than GI drop (23.7 [16.4-35.7] and 9.0 [6.0-12.0]; P < .01). There were correlations between the initial LI elevation and LI drop (R 2 = 0.466, P < .01) and between the LI and GI drop (R 2 = 0.263, P < .01). The LI drops significantly differed according to the different anatomical localizations by the Kruskal-Wallis test, although the GI drops did not differ (P < .01 and P = .49, respectively).

CONCLUSION

LI drop was associated with initial LI elevation and was larger than GI drop. LI drop was different according to locations, although GI drop was not. These findings might indicate that LI drop would be a more sensitive marker for lesion formation than GI drop.

Left Ventricular Diastolic Dysfunction Is Associated With the Prevalence of Paroxysmal Atrial Fibrillation Determined on the Latest Echocardiographic Criteria

Background: The relationship between left ventricular diastolic dysfunction (LVDD) and paroxysmal atrial fibrillation (PAF) remains unclear because of a lack of standard measures to evaluate LVDD. Accordingly, we examined the association between the prevalence of PAF and each LVDD grade determined according to the latest American Society of Echocardiography guidelines.

Methods and Results: In all, 2,063 patients without persistent AF who underwent echocardiography at Saitama Municipal Hospital from July 2016 to June 2017 were included in the study. Patients were divided into LVDD 6 categories: No-LVDD (n=1,107), Borderline (n=392), Grade 1 (n=204), Indeterminate (n=62), Grade 2 (n=254), and Grade 3 (n=44). PAF was documented in 111 (10.0%), 81 (20.7%), 28 (13.7%), 6 (9.7%), 52 (20.5%), and 24 (54.5%) patients in the No-LVDD, Borderline, Grade 1, Indeterminate, Grade 2, and Grade 3 categories, respectively. PAF prevalence was higher in patients with Grade 3 LVDD across the whole study population. Subgroup analyses showed that the prevalence of PAF increased with increased LVDD grade in patients with reduced left ventricular ejection fraction. This relationship was significant in multivariate analysis including various patient characteristics.

Conclusions: LVDD severity determined on the basis of the latest echocardiographic criteria was associated with the prevalence of PAF. The present findings shed light on the development of new therapeutic markers for PAF.

c.753A>G genome editing of a Cdh23ahl allele delays age-related hearing loss and degeneration of cochlear hair cells in C57BL/6J mice

C57BL/6J mice have long been studied as a model of age-related hearing loss (ARHL). In C57BL/6J mice, ARHL begins in the high-frequency range at 3 months of age and spreads toward low frequencies by 10 months of age. We previously confirmed that c.753A>G genome editing of an ahl allele (c.753A) in the cadherin 23 gene (Cdh23) suppressed the onset of ARHL until 12 months of age. We further investigated the hearing phenotypes of the original and genome-edited C57BL/6J-Cdh23^+/+ (c.753G/G) mice until 24 months of age. The hearing tests revealed that most of the C57BL/6J mice maintained good hearing levels until 14 months of age following genome editing of a Cdh23^ahl allele. However, the hearing levels of the C57BL/6J-Cdh23^+/+ mice gradually declined, and severe ARHL developed with increasing age. ARHL in the C57BL/6J mice was correlated with degeneration of the stereocilia in cochlear hair cells. The stereocilia degeneration was rescued in the C57BL/6J-Cdh23^+/+ mice at 12 months of age, but the stereocilia bundles exhibited abnormal phenotypes similar to those of the original C57BL/6J mice at more advanced ages. Therefore, genome editing of Cdh23^ahl did not completely suppress ARHL in C57BL/6J mice. We also compared the hearing levels of C57BL/6J-Cdh23^+/+ mice with those of C3H/HeN and MSM/Ms mice, which carry the Cdh23⁺ allele. The severity and onset patterns of ARHL in the C57BL/6J-Cdh23^+/+ mice differed from those observed in other Cdh23^+/+ mice. Therefore, we hypothesize that other susceptible and/or resistant alleles of ARHL exist in the genetic backgrounds of these mice.

Lower grip strength and dynamic body balance in women with distal radial fractures

In this case-control study, we concluded that women with distal radial fractures who were surgically treated showed lower grip strength and dynamic body balancing than those of controls. These results suggest that measurements of grip strength and dynamic body balance may be useful screening tools to assess future fracture risk.

INTRODUCTION

Patients with distal radial fractures (DRFs) are at risk of future fragility fractures. However, their physical characteristics and tendencies for falls remain unclear. We aimed to compare the physical characteristics of women with and without distal radial fractures.

METHODS

We included 128 women with a DRF as their first fragility fracture (fracture group) who underwent surgical treatment. Concurrently, 128 age- and sex-matched participants without a history of fragility fractures were selected as controls (control group). The participants underwent assessments of grip strength and the body balancing ability test. Measurements were taken twice in the fracture group, at 2 weeks and 6 months postoperatively, and once in the control group. The body balancing ability test included the Functional Reach Test, Timed Up and Go test (TUG), 2-Step test (2ST), and Timed Uni-pedal Stance test. The participants also completed questionnaires about their health.

RESULTS

There were no significant differences (p > 0.05) in patient characteristics between the groups. The fracture group showed lower grip strength across all age groups. In the DRF group, prolonged TUG time was observed at 2 weeks postoperatively in all age groups and at 6 months in participants aged 55-74 years; the 2ST score was significantly lower in participants aged between 65 and 74 years.

CONCLUSIONS

Women with DRF demonstrated lower grip strength and dynamic body balancing ability. Lower grip strength and dynamic body balancing ability were identified as significant risk factors in women with DRF, suggesting that these may be useful screening tools to assess fracture risk.

Correction to: Lower grip strength and dynamic body balance in women with distal radial fractures

The article Lower grip strength and dynamic body balance in women with distal radial fractures, written by. K. Fujita, H. Kaburagi, A. Nimura, T. Miyamoto, Y. Wakabayashi, Y. Seki, H. Aoyama, H. Shimura, R. Kato, A. Okawa was originally published electronically on the publisher's internet portal.

Distal locking screw length for volar locking plate fixation of distal radius fractures: Postoperative stability of full-length unicortical versus shorter screws

We compared post-operative distal radius fracture (DRF) displacement after volar locking plate fixation using full-length unicortical and shorter-length distal locking screws. In this non-inferiority, retrospective cohort study, DRFs treated with volar locking plate fixation were evaluated on X-rays. In the full-length group, volar locking plate fixation was performed with full-length unicortical distal locking screws. In the shorter-length group, the distal locking screws were planned pre-operatively to be approximately 75% of the distal radius depth based on the lunate depth, and the same depth was drilled. Three radiographic parameters - ulnar variance, volar tilt, and radial inclination - were measured intra-operatively and at the final follow-up. The displacements were compared between the two groups. Each group contained 34 fractures. The mean ulnar variance between the two periods increased 1.1 mm in the full-length group and 1.3 mm in the shorter group (mean difference, 0.2 mm; 90% confidence interval, -0.3 to 0.6). The shorter group was not significantly inferior to the full-length one. Volar tilt increased 0.6° in the full-length group and -0.1° in the shorter group, while the radial inclination increased 0.1° in the full-length group and 0.2° in the shorter one. The differences in the increases were not significant. The post-operative DRF stability of 75%-length distal locking screws was not inferior to that of full-length unicortical screws. To prevent extensor pollicis longus tendon rupture, shorter distal locking screws and the same drilling depth may be preferable for volar locking plate fixation.

Clinical features and treatment of nonalcoholic fatty liver disease across the Asia Pacific region-the GO ASIA initiative

BACKGROUND

The Gut and Obesity Asia (GO ASIA) workgroup was formed to study the relationships between obesity and gastrointestinal diseases in the Asia Pacific region.

AIM

To study factors associated with nonalcoholic steatohepatitis (NASH) and advanced fibrosis, and medical treatment of biopsy-proven nonalcoholic fatty liver disease (NAFLD) patients.

METHODS

Retrospective study of biopsy-proven NAFLD patients from centres in the GO ASIA Workgroup. Independent factors associated with NASH and with advanced fibrosis on binary logistic regression analyses in a training cohort were used for the development of their corresponding risk score, which were validated in a validation cohort.

RESULTS

We included 1008 patients from nine centres across eight countries (NASH 62.9%, advanced fibrosis 17.2%). Independent predictors of NASH were body mass index ≥30 kg/m² , diabetes mellitus, dyslipidaemia, alanine aminotransferase ≥88 U/L and aspartate aminotransferase ≥38 U/L, constituting the Asia Pacific NASH risk score. A high score has a positive predictive value of 80%-83% for NASH. Independent predictors of advanced fibrosis were age ≥55 years, diabetes mellitus and platelet count <150 × 10⁹ /L, constituting the Asia-Pacific NAFLD advanced fibrosis risk score. A low score has a negative predictive value of 95%-96% for advanced fibrosis. Only 1.7% of patients were referred for structured lifestyle program, 4.2% were on vitamin E, and 2.4% were on pioglitazone.

CONCLUSIONS

More severe liver disease can be suspected or ruled out based on factors identified in this study. Utilisation of structured lifestyle program, vitamin E and pioglitazone was limited despite this being a cohort of biopsy-proven NAFLD patients with majority of patients having NASH.

Pde6brd1 mutation modifies cataractogenesis in Foxe3rct mice

The Foxe3^rct mutation, which causes early-onset cataracts, is a recessive mutation found in SJL/J mice. A previous study reported that cataract phenotypes are modified by the genetic background of mouse inbred strains and that the Pde6b^rd1 mutation, which induced degeneration of the photoreceptor cells, is a strong candidate genetic modifier to accelerate the severity of cataractogenesis of Foxe3^rct mice. We created congenic mice by transferring a genomic region including the Foxe3^rct mutation to the B6 genetic background, which does not carry the Pde6b^rd1 mutation. In the congenic mice, the cataract phenotypes became remarkably mild, and the development of cataracts was suppressed for a long time. Moreover, we created transgenic mice by injecting BAC clones including the wild-type Pde6b gene into the eggs of SJL-Foxe3^rct mice. Although the resistant effect for cataract phenotypes in transgenic mice was less than that in congenic mice, the severity and onset time of cataract phenotypes were clearly improved and delayed, respectively, compared with the phenotypes of the original SJL-Foxe3^rct mice. These results clearly show that the development of early-onset cataracts requires at least two mutant alleles of Foxe3^rct and Pde6b^rd1, and another modifier associated with the severity of cataract phenotypes in Foxe3^rct mice underlies the genetic backgrounds in mice.

Evaluation of swallowing ability using swallowing sounds in maxillectomy patients

Maxillectomy for oral tumours often results in debilitating oral hypofunction, which markedly decreases quality of life. Dysphagia, in particular, is one of the most serious problems following maxillectomy. This study used swallowing sounds as a simple evaluation method to evaluate swallowing ability in maxillectomy patients with and without their obturator prosthesis placed. Twenty-seven maxillectomy patients (15 men, 12 women; mean age 66.0 ± 12.1 years) and 30 healthy controls (14 men, 16 women; mean age 44.9 ± 21.3 years) were recruited for this study. Participants were asked to swallow 4 mL of water, and swallowing sounds were recorded using a throat microphone. Duration of the acoustic signal and duration of peak intensity (DPI) were measured. Duration of peak intensity was significantly longer in maxillectomy patients without their obturator than with it (P < .05) and was significantly longer in maxillectomy patients without their obturator than in healthy controls (P < .025 after Bonferroni correction). With the obturator placed, DPI was significantly longer in maxillectomy patients who had undergone soft palate resection than in those who had not (P < .05). These results suggest swallowing ability in maxillectomy patients could be improved by wearing an obturator prosthesis, particularly during the oral stage. However, it is difficult to improve the oral stage of swallowing in patients who have undergone soft palate resection even with obturator placement.

A novel splice site mutation of myosin VI in mice leads to stereociliary fusion caused by disruption of actin networks in the apical region of inner ear hair cells

An unconventional myosin encoded by the myosin VI gene (MYO6) contributes to hearing loss in humans. Homozygous mutations of MYO6 result in nonsyndromic profound congenital hearing loss, DFNB37. Kumamoto shaker/waltzer (ksv) mice harbor spontaneous mutations, and homozygous mutants exhibit congenital defects in balance and hearing caused by fusion of the stereocilia. We identified a Myo6^c.1381G>A mutation that was found to be a p.E461K mutation leading to alternative splicing errors in Myo6 mRNA in ksv mutants. An analysis of the mRNA and protein expression in animals harboring this mutation suggested that most of the abnormal alternatively spliced isoforms of MYO6 are degraded in ksv mice. In the hair cells of ksv/ksv homozygotes, the MYO6 protein levels were significantly decreased in the cytoplasm, including in the cuticular plates. MYO6 and stereociliary taper-specific proteins were mislocalized along the entire length of the stereocilia of ksv/ksv mice, thus suggesting that MYO6 attached to taper-specific proteins at the stereociliary base. Histological analysis of the cochlear hair cells showed that the stereociliary fusion in the ksv/ksv mutants, developed through fusion between stereociliary bundles, raised cuticular plate membranes in the cochlear hair cells and resulted in incorporation of the bundles into the sheaths of the cuticular plates. Interestingly, the expression of the stereociliary rootlet-specific TRIO and F-actin binding protein (TRIOBP) was altered in ksv/ksv mice. The abnormal expression of TRIOBP suggested that the rootlets in the hair cells of ksv/ksv mice had excessive growth. Hence, these data indicated that decreased MYO6 levels in ksv/ksv mutants disrupt actin networks in the apical region of hair cells, thereby maintaining the normal structure of the cuticular plates and rootlets, and additionally provided a cellular basis for stereociliary fusion in Myo6 mutants.

A novel missense mutation of Mip causes semi-dominant cataracts in the Nat mouse

Major intrinsic protein of lens fiber (MIP) is one of the proteins essential for maintaining lens transparency while also contributing to dominant cataracts in humans. The Nodai cataract (Nat) mice harbor a spontaneous mutation in Mip and develop early-onset nuclear cataracts. The Nat mutation is a c.631G>A mutation (Mip^Nat), resulting in a glycine-to-arginine substitution (p.Gly211Arg) in the sixth transmembrane domain. The Mip^Nat/Nat homozygotes exhibit congenital cataracts caused by the degeneration of lens fiber cells. MIP normally localizes to the lens fiber cell membranes. However, the Mip^Nat/Nat mice were found to lack an organelle-free zone, and the MIP was mislocalized to the nuclear membrane and perinuclear region. Furthermore, the Mip^Nat/+ mice exhibited milder cataracts than Mip^Nat/Nat mice due to the slight degeneration of the lens fiber cells. Although there were no differences in the localization of MIP to the membranes of lens fiber cells in Mip^Nat/+ mice compared to that in wild-type mice, the protein levels of MIP were significantly reduced in the eyes. These findings suggest that cataractogenesis in Mip^Nat mutants are caused by defects in MIP expression. Overall, the Mip^Nat mice offer a novel model to better understand the phenotypes and mechanisms for the development of cataracts in patients that carry missense mutations in MIP.

Why chronically ill children face challenges in regular classrooms: perspectives from nursing teachers in Japan

BACKGROUND

Chronically ill children are increasingly expected to join their peers in regular classrooms. However, sometimes schools do not provide adequate assistance. This study explores nursing teachers' thoughts and experiences on integrating such students into regular classrooms in Japan.

METHODS

We analysed 79 essays written by nursing teachers collectively titled 'The challenges of having chronically ill children in regular classrooms'. We conducted a qualitative study using Kinoshita's Modified Grounded Theory Approach.

RESULTS

Nursing teachers identified three main obstacles: insufficient resources to support chronically ill students, parents not playing a supporting role in aiding them at school and a regular classroom not being suitable for them. However, collaborating with the children's medical staff proved successful at integrating them into regular classrooms.

CONCLUSIONS

Given these obstacles, it seems very difficult for nursing teachers to lead the way toward establishing cooperative support systems for the children. Instructions from medical staff could empower teachers to set up such systems.

Characterization and application of newly developed polymorphic microsatellite markers in the Ezo red fox (Vulpes vulpes schrencki)

The Ezo red fox (Vulpes vulpes schrencki), a subspecies endemic to Hokkaido island, Japan, is a known host species for the tapeworm Echinococcus multilocularis. To develop tools for molecular ecological studies, we isolated 28 microsatellite regions from the genome of Ezo red fox, and developed 18 polymorphic microsatellite markers. These markers were characterized using 7 individuals and 22 fecal samples of the Ezo red fox. The number of alleles for these markers ranged from 1 to 7, and the observed heterozygosity, estimated on the basis of the genotypes of 7 individuals, ranged from 0.29 to 1.00. All markers, except DvNok5, were in Hardy-Weinberg equilibrium (P > 0.05), and no linkage disequilibrium was detected among these loci, except between DvNok14 and DvNok28 (P = 0.01). Moreover, six microsatellite loci were successfully genotyped using feces-derived DNA from the Ezo red fox. The markers developed in our study might serve as a useful tool for molecular ecological studies of the Ezo red fox.

Heterozygous mutation of Ush1g/Sans in mice causes early-onset progressive hearing loss, which is recovered by reconstituting the strain-specific mutation in Cdh23

Most clinical reports have suggested that patients with congenital profound hearing loss have recessive mutations in deafness genes, whereas dominant alleles are associated with progressive hearing loss (PHL). Jackson shaker (Ush1g^js) is a mouse model of recessive deafness that exhibits congenital profound deafness caused by the homozygous mutation of Ush1g/Sans on chromosome 11. We found that C57BL/6J-Ush1g^js/+ heterozygous mice exhibited early-onset PHL (ePHL) accompanied by progressive degeneration of stereocilia in the cochlear outer hair cells. Interestingly, ePHL did not develop in mutant mice with the C3H/HeN background, thus suggesting that other genetic factors are required for ePHL development. Therefore, we performed classical genetic analyses and found that the occurrence of ePHL in Ush1g^js/+ mice was associated with an interval in chromosome 10 that contains the cadherin 23 gene (Cdh23), which is also responsible for human deafness. To confirm this mutation effect, we generated C57BL/6J-Ush1g^js/+, Cdh23^c.753A/G double-heterozygous mice by using the CRISPR/Cas9-mediated Cdh23^c.753A>G knock-in method. The Cdh23^c.753A/G mice harbored a one-base substitution (A for G), and the homozygous A allele caused moderate hearing loss with aging. Analyses revealed the complete recovery of ePHL and stereocilia degeneration in C57BL/6J-Ush1g^js/+ mice. These results clearly show that the development of ePHL requires at least two mutant alleles of the Ush1g and Cdh23 genes. Our results also suggest that because the SANS and CDH23 proteins form a complex in the stereocilia, the interaction between these proteins may play key roles in the maintenance of stereocilia and the prevention of ePHL.

Judging hardness of an object from the sounds of tapping created by a white cane

The white cane plays a vital role in the independent mobility support of the visually impaired. Allowing the recognition of target attributes through the contact of a white cane is an important function. We have conducted research to obtain fundamental knowledge concerning the exploration methods used to perceive the hardness of an object through contact with a white cane. This research has allowed us to examine methods that enhance accuracy in the perception of objects as well as the materials and structures of a white cane. Previous research suggest considering the roles of both auditory and tactile information from the white cane in determining objects' hardness is necessary. This experimental study examined the ability of people to perceive the hardness of an object solely through the tapping sounds of a white cane (i.e., auditory information) using a method of magnitude estimation. Two types of sounds were used to estimate hardness: 1) the playback of recorded tapping sounds and 2) the sounds produced on-site by tapping. Three types of handgrips were used to create different sounds of tapping on an object with a cane. The participants of this experiment were five sighted university students wearing eye masks and two totally blind students who walk independently with a white cane. The results showed that both sighted university students and totally blind participants were able to accurately judge the hardness of an object solely by using auditory information from a white cane. For the blind participants, different handgrips significantly influenced the accuracy of their estimation of an object's hardness.

Are tyrosine residues involved in the photoconversion of the water-soluble chlorophyll-binding protein of Chenopodium album?

Non-photosynthetic and hydrophilic chlorophyll (Chl) proteins, called water-soluble Chl-binding proteins (WSCPs), are distributed in various species of Chenopodiaceae, Amaranthaceae, Polygonaceae and Brassicaceae. Based on their photoconvertibility, WSCPs are categorised into two classes: Class I (photoconvertible) and Class II (non-photoconvertible). Chenopodium album WSCP (CaWSCP; Class I) is able to convert the chlorin skeleton of Chl a into a bacteriochlorin-like skeleton under light in the presence of molecular oxygen. Potassium iodide (KI) is a strong inhibitor of the photoconversion. Because KI attacks tyrosine residues in proteins, tyrosine residues in CaWSCP are considered to be important amino acid residues for the photoconversion. Recently, we identified the gene encoding CaWSCP and found that the mature region of CaWSCP contained four tyrosine residues: Tyr13, Tyr14, Tyr87 and Tyr134. To gain insight into the effect of the tyrosine residues on the photoconversion, we constructed 15 mutant proteins (Y13A, Y14A, Y87A, Y134A, Y13-14A, Y13-87A, Y13-134A, Y14-87A, Y14-134A, Y87-134A, Y13-14-87A, Y13-14-134A, Y13-87-134A, Y14-87-134A and Y13-14-87-134A) using site-directed mutagenesis. Amazingly, all the mutant proteins retained not only chlorophyll-binding activity, but also photoconvertibility. Furthermore, we found that KI strongly inhibited the photoconversion of Y13-14-87-134A. These findings indicated that the four tyrosine residues are not essential for the photoconversion.

Disclosing haemophilia at school: strategies employed by mothers of children with haemophilia in Japan

INTRODUCTION

Most children with haemophilia in Japan study in mainstream schools. However, many mothers have difficulty deciding whether to inform teachers of their child's haemophilia because of the accompanying potential discrimination and prejudice, particularly after the press coverage on the HIV scandal in the 1980s.

AIMS

We therefore aim to explore and describe disclosure strategies of mothers of children with haemophilia.

METHODS

A qualitative study was conducted using the modified grounded theory approach to explore disclosure strategies of mothers of children with haemophilia. Semi-structured interviews were conducted with 19 selected mothers (12 children were HIV positive and 7 were HIV-negative).

RESULTS

In the pre-HIV/AIDS crisis period, the kind of strategy employed - full disclosure, conditional full disclosure and partial disclosure - depended on the extent of mothers' fears about mainstream schools refusing admission because of their child's haemophilia. After the HIV/AIDS crisis in the 1980s in Japan, the three categories of strategies employed by mothers of children with haemophilia were limited disclosure, non-disclosure and full disclosure. These depended on mothers' expectations of discrimination towards their child because of the social stigma around haemophilia and being HIV-positive.

CONCLUSION

For children with haemophilia to feel safe attending school, public schools must establish care management and anti-discrimination systems for children with chronic diseases, thus assuring parents of their children's welfare at school.

Neurotransmitters, psychotropic drugs and microglia: clinical implications for psychiatry

Psychiatric disorders have long and dominantly been regarded to be induced by disturbances of neuronal networks including synapses and neurotransmitters. Thus, the effects of psychotropic drugs such as antipsychotics and antidepressants have been understood to modulate synaptic regulation via receptors and transporters of neurotransmitters such as dopamine and serotonin. Recently, microglia, immunological/inflammatory cells in the brain, have been indicated to have positive links to psychiatric disorders. Positron emission tomography (PET) imaging and postmortem studies have revealed microglial activation in the brain of neuropsychiatric disorders such as schizophrenia, depression and autism. Animal models of neuropsychiatric disorders have revealed the underlying microglial pathologies. In addition, various psychotropic drugs have been suggested to have direct effects on microglia. Until now, the relationship between microglia, neurotransmitters and psychiatric disorders has not been well understood. Therefore, in this review, at first, we summarize recent findings of interaction between microglia and neurotransmitters such as dopamine, serotonin, norepinephrine, acetylcholine and glutamate. Next, we introduce up-to-date knowledge of the effects of psychotropic drugs such as antipsychotics, antidepressants and antiepileptics on microglial modulation. Finally, we propose the possibility that modulating microglia may be a key target in the treatment of various psychiatric disorders. Further investigations and clinical trials should be conducted to clarify this perspective, using animal in vivo studies and imaging studies with human subjects.

Observation of polyphosphate bodies and DNA during the cell division cycle of Synechococcus elongatus PCC 7942

Although most cyanobacterial cells contain prominent polyphosphate bodies in the central cytoplasmic area enclosed by the peripheral thylakoid membranes, their roles are not fully understood. Storing phosphate for nucleotide production might be one of their important roles in survival of the cells. As a step towards identifying a possible contribution of the polyphosphate bodies to DNA synthesis, the relationship between polyphosphate bodies and DNA throughout cell division cycle of Synechococcus elongatus PCC 7942 cells cultured under light/dark cycles was investigated with light and electron microscopy. During the dark period, the average size of polyphosphate bodies increased gradually without significant change in their number and distribution. However, during the light period, the number of polyphosphate bodies increased, while the size of each polyphosphate body decreased and cells elongated until the end of the light period, when most cells divided. The ratio of the content of polyphosphate bodies to cell length increased gradually during the dark period and decreased during the light period. Hoechst 33342-stained DNA appeared diffuse during the dark period, but in the light period it became condensed and eventually formed a wavy, rope-like structure prior to cell division. Close association between fibres containing DNA and polyphosphate bodies was demonstrated by TEM using DNA-specific staining and BrdU labelling. These regular coordinated changes of polyphosphate bodies and DNA shape during the cell division cycle, together with their intimate interaction, imply a role of polyphosphate bodies in supplying material for DNA.

Development of an animal model to study congenital urinary obstruction

PURPOSE

We outline the development of a reliable model of obstructive uropathy in fetal lambs highlighting our understanding of the critical time points for interventions and the variability of any such model. We identify some discoveries that may have clinical implications.

METHODS

The model requires 60-day-gestation fetal lambs. In lambs, glomerulogenesis is complete by 90 days gestation. (Term is 145 days.) The ability to develop a reliable method of creating bladder outlet obstruction in females, ligating both the urethra and urachus was critical. The lambs are bred to an accuracy of ±24 h.

RESULTS

Creating the model at 50-60 days gestation, produces different expressions of renal dysplasia in groups of lambs undergoing identical interventions at the same stage of gestation. Early complete urethral obstruction can produce the Potter phenotype. An appropriately timed vesico-amniotic shunt preserves renal development, producing a shrunken, non-compliant bladder. Shunting the normal fetal bladder at 80 days gestation produces a similar bladder. Provision of a low-pressure valve in the shunt preserves bladder development and compliance. Using a high-pressure shunt produces results similar to non-shunted lambs.

DISCUSSION

We developed a reliable animal model for obstructive uropathy. Being alert to peripheral results can lead to new findings.