Significant increase in the prevalence of Panton-Valentine leukocidin-positive methicillin-resistant Staphylococcus aureus, particularly the USA300 variant ΨUSA300, in the Japanese community

IMPORTANCE

USA300 is an MRSA clone producing PVL, a toxin associated with SSTIs. ΨUSA300 is a USA300 variant recently identified in Japan by Takadama et al. (15). Here, we found that the prevalence rate of PVL-positive MRSA in S. aureus was elevated in the Japanese community, and ΨUSA300 accounted for most of them. ΨUSA300 strains have been isolated from several areas in Japan and were associated with deep-seated SSTIs. This study highlighted the emerging threat posed by ΨUSA300 in Japan.

ORF3c is expressed in SARS-CoV-2-infected cells and inhibits innate sensing by targeting MAVS

Most SARS-CoV-2 proteins are translated from subgenomic RNAs (sgRNAs). While the majority of these sgRNAs are monocistronic, some viral mRNAs encode more than one protein. One example is the ORF3a sgRNA that also encodes ORF3c, an enigmatic 41-amino-acid peptide. Here, we show that ORF3c is expressed in SARS-CoV-2-infected cells and suppresses RIG-I- and MDA5-mediated IFN-β induction. ORF3c interacts with the signaling adaptor MAVS, induces its C-terminal cleavage, and inhibits the interaction of RIG-I with MAVS. The immunosuppressive activity of ORF3c is conserved among members of the subgenus sarbecovirus, including SARS-CoV and coronaviruses isolated from bats. Notably, however, the SARS-CoV-2 delta and kappa variants harbor premature stop codons in ORF3c, demonstrating that this reading frame is not essential for efficient viral replication in vivo and is likely compensated by other viral proteins. In agreement with this, disruption of ORF3c does not significantly affect SARS-CoV-2 replication in CaCo-2, CaLu-3, or Rhinolophus alcyone cells. In summary, we here identify ORF3c as an immune evasion factor of SARS-CoV-2 that suppresses innate sensing in infected cells.

Determination of the factors responsible for the tropism of SARS-CoV-2-related bat coronaviruses to Rhinolophus bat ACE2

IMPORTANCE

The efficiency of infection receptor use is the first step in determining the species tropism of viruses. After the coronavirus disease 2019 pandemic, a number of SARS-CoV-2-related coronaviruses (SC2r-CoVs) were identified in Rhinolophus bats, and some of them can use human angiotensin converting enzyme 2 (ACE2) for the infection receptor without acquiring additional mutations. This means that the potential of certain SC2r-CoVs to cause spillover from bats to humans is "off-the-shelf." However, both SC2r-CoVs and Rhinolophus bat species are highly diversified, and the host tropism of SC2r-CoVs remains unclear. Here, we focus on two Laotian SC2r-CoVs, BANAL-20-236 and BANAL-20-52, and determine how the tropism of SC2r-CoVs to Rhinolophus bat ACE2 is determined at the amino acid resolution level.

Multiple mutations of SARS-CoV-2 Omicron BA.2 variant orchestrate its virological characteristics

IMPORTANCE

Most studies investigating the characteristics of emerging SARS-CoV-2 variants have been focusing on mutations in the spike proteins that affect viral infectivity, fusogenicity, and pathogenicity. However, few studies have addressed how naturally occurring mutations in the non-spike regions of the SARS-CoV-2 genome impact virological properties. In this study, we proved that multiple SARS-CoV-2 Omicron BA.2 mutations, one in the spike protein and another downstream of the spike gene, orchestrally characterize this variant, shedding light on the importance of Omicron BA.2 mutations out of the spike protein.

Impact of Imprinted Immunity Induced by mRNA Vaccination in an Experimental Animal Model

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variants has led to concerns that ancestral SARS-CoV-2-based vaccines may not be effective against newly emerging Omicron subvariants. The concept of "imprinted immunity" suggests that individuals vaccinated with ancestral virus-based vaccines may not develop effective immunity against newly emerging Omicron subvariants, such as BQ.1.1 and XBB.1. In this study, we investigated this possibility using hamsters. Although natural infection induced effective antiviral immunity, breakthrough infections in hamsters with BQ.1.1 and XBB.1 Omicron subvariants after receiving the 3-dose mRNA-lipid nanoparticle vaccine resulted in only faintly induced humoral immunity, supporting the possibility of imprinted immunity.

Comparison of short-term outcomes of robotic and laparoscopic transabdominal peritoneal repair for unilateral inguinal hernia: a propensity-score matched analysis

PURPOSE

This study aimed to compare perioperative outcomes of robotic and laparoscopic transabdominal peritoneal repair (TAPP) for unilateral inguinal hernia.

METHODS

This single institutional retrospective cohort study used de-identified data of patients who underwent robotic TAPP (R-TAPP) or laparoscopic TAPP (L-TAPP) for unilateral inguinal hernia between January 1, 2016 and October 31, 2021. Two cohorts were propensity matched, and data were analyzed. The learning curve was evaluated in the R-TAPP group.

RESULTS

Among 938 patients analyzed, 704 were included. After propensity-score matching, 80 patients were included in each group. The difference in operative time between R-TAPP and L-TAPP groups was 10 min (99.5 and 89.5 min, p = 0.087); however, console/laparoscopic time was similar (67 and 66 min, p = 0.71). The dissection time for medial-type hernia in the R-TAPP group was marginally shorter than that in the L-TAPP group (17 and 27 min, p = 0.056); however, there was no difference for lateral-type hernia (38.5 and 40 min p = 0.37). Perioperative variables, including estimated blood loss, postoperative hospital stay, and postoperative pain, had no significant difference, and chronic pain, which needed medication or intervention, was not observed in each group. The number of cases needed to achieve plateau performance was 7-10 in the R-TAPP group.

CONCLUSION

This study suggests that R-TAPP was safely introduced, and its perioperative outcomes were not inferior to those of L-TAPP. A shorter dissection time for medial-type hernia might be due to the robot's advantages, and a fast-learning curve could help with the early standardization of the procedure.

Virological characteristics of the SARS-CoV-2 XBB variant derived from recombination of two Omicron subvariants

In late 2022, SARS-CoV-2 Omicron subvariants have become highly diversified, and XBB is spreading rapidly around the world. Our phylogenetic analyses suggested that XBB emerged through the recombination of two cocirculating BA.2 lineages, BJ.1 and BM.1.1.1 (a progeny of BA.2.75), during the summer of 2022. XBB.1 is the variant most profoundly resistant to BA.2/5 breakthrough infection sera to date and is more fusogenic than BA.2.75. The recombination breakpoint is located in the receptor-binding domain of spike, and each region of the recombinant spike confers immune evasion and increases fusogenicity. We further provide the structural basis for the interaction between XBB.1 spike and human ACE2. Finally, the intrinsic pathogenicity of XBB.1 in male hamsters is comparable to or even lower than that of BA.2.75. Our multiscale investigation provides evidence suggesting that XBB is the first observed SARS-CoV-2 variant to increase its fitness through recombination rather than substitutions.

Convergent evolution of SARS-CoV-2 Omicron subvariants leading to the emergence of BQ.1.1 variant

In late 2022, various Omicron subvariants emerged and cocirculated worldwide. These variants convergently acquired amino acid substitutions at critical residues in the spike protein, including residues R346, K444, L452, N460, and F486. Here, we characterize the convergent evolution of Omicron subvariants and the properties of one recent lineage of concern, BQ.1.1. Our phylogenetic analysis suggests that these five substitutions are recurrently acquired, particularly in younger Omicron lineages. Epidemic dynamics modelling suggests that the five substitutions increase viral fitness, and a large proportion of the fitness variation within Omicron lineages can be explained by these substitutions. Compared to BA.5, BQ.1.1 evades breakthrough BA.2 and BA.5 infection sera more efficiently, as demonstrated by neutralization assays. The pathogenicity of BQ.1.1 in hamsters is lower than that of BA.5. Our multiscale investigations illuminate the evolutionary rules governing the convergent evolution for known Omicron lineages as of 2022.

Identification and characterization of the genome of a papillomavirus from skin lesions of four-toed hedgehogs (Atelerix albiventris)

The present study describes the clinical and pathological characteristics of skin lesions in two four-toed hedgehogs (Atelerix albiventris). We performed inverse PCR to identify the genome of papillomavirus (PV) in the skin lesions and subsequently sequenced the full genome of the virus, which was tentatively named Atelerix albiventris papillomavirus 1 (AalbPV1). The overall sequences of the viral genomes of both four-toed hedgehogs were identical. This study first identified the presence of a novel PV in Japanese four-toed hedgehogs and provided genetic information about this virus.

Structural Insight into the Resistance of the SARS-CoV-2 Omicron BA.4 and BA.5 Variants to Cilgavimab

We have recently revealed that the new SARS-CoV-2 Omicron sublineages BA.4 and BA.5 exhibit increased resistance to cilgavimab, a therapeutic monoclonal antibody, and the resistance to cilgavimab is attributed to the spike L452R substitution. However, it remains unclear how the spike L452R substitution renders resistance to cilgavimab. Here, we demonstrated that the increased resistance to cilgavimab of the spike L452R is possibly caused by the steric hindrance between cilgavimab and its binding interface on the spike. Our results suggest the importance of developing therapeutic antibodies that target SARS-CoV-2 variants harboring the spike L452R substitution.

Virological characteristics of the SARS-CoV-2 Omicron BA.2.75 variant

The SARS-CoV-2 Omicron BA.2.75 variant emerged in May 2022. BA.2.75 is a BA.2 descendant but is phylogenetically distinct from BA.5, the currently predominant BA.2 descendant. Here, we show that BA.2.75 has a greater effective reproduction number and different immunogenicity profile than BA.5. We determined the sensitivity of BA.2.75 to vaccinee and convalescent sera as well as a panel of clinically available antiviral drugs and antibodies. Antiviral drugs largely retained potency, but antibody sensitivity varied depending on several key BA.2.75-specific substitutions. The BA.2.75 spike exhibited a profoundly higher affinity for its human receptor, ACE2. Additionally, the fusogenicity, growth efficiency in human alveolar epithelial cells, and intrinsic pathogenicity in hamsters of BA.2.75 were greater than those of BA.2. Our multilevel investigations suggest that BA.2.75 acquired virological properties independent of BA.5, and the potential risk of BA.2.75 to global health is greater than that of BA.5.

Virological characteristics of the SARS-CoV-2 Omicron BA.2 subvariants, including BA.4 and BA.5

After the global spread of the SARS-CoV-2 Omicron BA.2, some BA.2 subvariants, including BA.2.9.1, BA.2.11, BA.2.12.1, BA.4, and BA.5, emerged in multiple countries. Our statistical analysis showed that the effective reproduction numbers of these BA.2 subvariants are greater than that of the original BA.2. Neutralization experiments revealed that the immunity induced by BA.1/2 infections is less effective against BA.4/5. Cell culture experiments showed that BA.2.12.1 and BA.4/5 replicate more efficiently in human alveolar epithelial cells than BA.2, and particularly, BA.4/5 is more fusogenic than BA.2. We further provided the structure of the BA.4/5 spike receptor-binding domain that binds to human ACE2 and considered how the substitutions in the BA.4/5 spike play roles in ACE2 binding and immune evasion. Moreover, experiments using hamsters suggested that BA.4/5 is more pathogenic than BA.2. Our multiscale investigations suggest that the risk of BA.2 subvariants, particularly BA.4/5, to global health is greater than that of original BA.2.

Identification of amino acid substitutions escaping from a broadly neutralizing monoclonal antibody of feline calicivirus

Feline calicivirus (FCV) causes upper respiratory tract diseases in cats and has highly variable antigenicity for neutralization of each strain. Neutralizing epitopes of FCV are currently found in the hypervariable region (HVR) in the P2 domain of the major capsid protein VP1. Due to its unique ability to neutralize various FCV strains, 1D7 is a monoclonal antibody that may recognize a novel neutralizing epitope. While other neutralizing epitopes were characterized by producing neutralization-resistant variants, only 1D7-resistant variants could not be obtained, and its epitope has not been identified in the previous studies. In this study, we successfully generated these variants by multiple passaging of the FCV F4 strain in the presence of 1D7 and discovered that several amino acid substitutions (K638N, R662G, and T666I in the P1 domain of VP1) are involved in the decreased binding of 1D7. These substitution sites are also highly conserved among FCV strains compared with the substitution sites of other neutralization-resistant variants found in the HVR. Our results indicate that amino acid substitutions in the P1 domain, which are not responsible for direct interaction with the FCV receptor, are associated with neutralization escape. Since FCV can be conveniently cultured in vitro and the receptor required for infection is known, a detailed analysis of the 1D7 epitope could shed more light on the neutralization mechanism of the epitopes of viruses belonging to the Caliciviridae.

Cost of illness of liver diseases in Japan

INTRODUCTION AND OBJECTIVES

Liver disease is characterized by the progression from hepatitis to cirrhosis, followed by liver cancer, i.e., a disease with a higher mortality rate as the disease progresses. To estimate the cost of illness (COI) of liver diseases, including viral hepatitis, cirrhosis, and liver cancer, and to determine the overall effect of expensive but effective direct-acting antivirals on the COI of liver diseases.

PATIENTS OR MATERIALS AND METHODS

Using a COI method from available government statistics data, we estimated the economic burden at 3-year intervals from 2002 to 2017.

RESULTS

The total COI of liver diseases was 1402 billion JPY in 2017. The COI of viral hepatitis, cirrhosis, and liver cancer showed a downward trend. Conversely, other liver diseases, including alcoholic liver disease and nonalcoholic steatohepatitis (NASH), showed an upward trend. The COI of hepatitis C continued to decline despite a sharp increase in drug unit prices between 2014 and 2017.

CONCLUSIONS

The COI of liver diseases in Japan has been decreasing for the past 15 years. In the future, a further reduction in patients with hepatitis C is expected, and even if the incidence of NASH and alcoholic liver disease increases, that of cirrhosis and liver cancer will likely continue to decrease.

Impact of transcatheter aortic valve implantation on coronary flow reserve by transthoracic Doppler echocardiography 1-year after the intervention in severe aortic stenosis patients

Background

Coronary flow reserve (CFR) which is one of indexes reflecting coronary microcirculation in patients without significant epicardial coronary lesions can be impaired in patients with severe aortic stenosis (AS). It has been shown that CFR is an independent predictor for future cardiovascular events in AS patients. Transcatheter aortic valve implantation (TAVI) has rapidly become widespread and is becoming the standard treatment for severe AS. This procedure may have a good effect on CFR due to reduction of severe afterload in patients with severe AS. Although the recent reports evaluated change in CFR immediately and 6 months after TAVI, it has not been evaluated whether impaired CFR improves 1-year after TAVI in AS patients with preserved left ventricular ejection fraction (LVEF).

Purpose

The purpose of the present study was to investigate whether impaired CFR improves 1-year after TAVI in severe AS patients with preserved LVEF.

Methods

The study population consists of consecutive 105 patients with severe AS undergoing TAVI. Exclusion criteria were atrial fibrillation, old myocardial infarction, history of coronary artery bypass grafting, significant lesions in the left anterior descending artery (LAD), moderate or severe mitral valve disease, history of valve replacement, LVEF <50% and preoperative CFR >2.2. CFR was obtained from coronary flow velocity by transthoracic echocardiography at rest and maximal hyperemia in LAD before, immediately and 1-year after TAVI. We compared CFR between before and after TAVI in the study patients who did not meet the exclusion criteria.

Results

After exclusion of 76 patients who met the exclusion criteria, the final study patients consist of 29 patients (8 male, 84.9±5.2 years). There was no significant difference in LVEF (61.3±3.4% vs 61.6±4.4%, P=0.667) and LV end-diastolic volume (LVEDVI; 58.2±9.2 mL/m2 vs 55.8±9.0 mL/m2, P=0.089) between before and immediately after TAVI. LVEF (61.0±2.8%, P=0.721) and LVEDVI (58.0±9.1 mL/m2, P=0.949) 1-year after TAVI were similar to those before TAVI. There was no significant difference in coronary flow velocity at rest between before and immediately after TAVI (27.4±8.9 vs 24.4±7.0 cm/s, P=0.051) and between before and 1-year after TAVI (25.9±8.3 cm/s, P=0.396). Coronary flow velocity at maximal hyperemia 1-year after TAVI significantly increased compared with that before TAVI (from 48.8±13.9 to 67.9±21.0 cm/s, P<0.001) while there was no significant difference between before and immediately after TAVI (52.0±12.0 cm/s, P=0.186). Impaired CFR before TAVI (1.82±0.28) increased immediately (2.03±0.39, P=0.009) and 1-year after TAVI (2.69±0.57, P<0.001).

Conclusions

The present results suggest that impaired CFR in patients with preserved LVEF improves 1-year after TAVI. TAVI may have a good effect on CFR in severe AS patients with preserved LVEF.

Funding Acknowledgement

Type of funding sources: None.

Patient safety management systems and activities related to promoting voluntary in-hospital reporting and mandatory national-level reporting for patient safety issues: A cross-sectional study

Both voluntary in-hospital reporting and mandatory national-level reporting systems for patient safety issues need to work well to develop a patient safety learning system that is effective in preventing the recurrence of adverse events. Some of the hospital systems and activities may increase voluntary in-hospital reporting and mandatory national-level reporting. This study aimed to identify the hospital systems and activities that increase voluntary in-hospital reporting and mandatory national-level reporting for patient safety issues. An anonymous mail survey of hospitals in Japan was conducted in 2017. The hospitals were selected by stratified random sampling according to number of beds. The survey examined the annual number of reported events in the voluntary in-hospital reporting system for patient safety and experience of reporting unexpected patient deaths possibly due to medical interventions to the mandatory national-level reporting system in the last 2 years. The relationship of the answer to the questions with the patient safety management systems and activities at each hospital was analyzed. The response rate was 18.8% (603/3,215). The number of in-hospital reports per bed was positively related to identifying events by referring complaints or questions of patients or family members, using root cause analysis for analyzing reported events, and developing manuals or case studies based on reported events, and negatively related to the unification and standardization of medical devices and equipment. The experience with mandatory national-level reporting of serious adverse events was positively related to identifying problematic cases by a person in charge of patient safety management from the in-hospital reporting system of complications and accidental symptoms. Enhanced feedback for reporters may promote voluntary in-hospital reporting of minor cases with low litigation risks. Developing an in-hospital mechanism that examines all serious complications and accidental symptoms may promote mandatory national-level reporting of serious adverse events with high litigation risks.

The geographical maldistribution of obstetricians and gynecologists in Japan

Background

In Japan, there is a large geographical maldistribution of obstetricians/gynecologists, with a high proportion of females. This study seeks to clarify how the increase in the proportion of female physicians affects the geographical maldistribution of obstetrics/gynecologists.

Methods

Governmental data of the Survey of Physicians, Dentists and Pharmacists between 1996 and 2016 were used. The Gini coefficient was used to measure the geographical maldistribution. We divided obstetricians/gynecologists into four groups based on age and gender: males under 40 years, females under 40 years, males aged 40 years and above, and females aged 40 years and above, and the time trend of the maldistribution and contribution of each group was evaluated.

Results

The maldistribution of obstetricians/gynecologists was found to be worse during the study period, with the Gini coefficient exceeding 0.400 in 2016. The contribution ratios of female physicians to the deterioration of geographical maldistribution have been increasing for those under 40 years and those aged 40 years and above. However, there was a continuous decrease in the Gini coefficient of the two groups.

Conclusions

The increase in the contribution ratio of the female physician groups to the Gini coefficient in obstetrics/gynecology may be due to the increased weight of these groups. The Gini coefficients of the female groups were also found to be on a decline. Although this may be because the working environment for female physicians improved or more female physicians established their practice in previously underserved areas, such a notion needs to be investigated in a follow-up study.

3D Quantitative Synthetic MRI in the Evaluation of Multiple Sclerosis Lesions

BACKGROUND AND PURPOSE

Synthetic MR imaging creates multiple contrast-weighted images based on a single time-efficient quantitative scan, which has been mostly performed for 2D acquisition. We assessed the utility of 3D synthetic MR imaging in patients with MS by comparing its diagnostic image quality and lesion volumetry with conventional MR imaging.

MATERIALS AND METHODS

Twenty-four patients with MS prospectively underwent 3D quantitative synthetic MR imaging and conventional T1-weighted, T2-weighted, FLAIR, and double inversion recovery imaging, with acquisition times of 9 minutes 3 seconds and 18 minutes 27 seconds for the synthetic MR imaging and conventional MR imaging sequences, respectively. Synthetic phase-sensitive inversion recovery images and those corresponding to conventional MR imaging contrasts were created for synthetic MR imaging. Two neuroradiologists independently assessed the image quality on a 5-point Likert scale. The numbers of cortical lesions and lesion volumes were quantified using both synthetic and conventional image sets.

RESULTS

The overall diagnostic image quality of synthetic T1WI and double inversion recovery images was noninferior to that of conventional images (P = .23 and .20, respectively), whereas that of synthetic T2WI and FLAIR was inferior to that of conventional images (both Ps < .001). There were no significant differences in the number of cortical lesions (P = .17 and .53 for each rater) or segmented lesion volumes (P = .61) between the synthetic and conventional image sets.

CONCLUSIONS

Three-dimensional synthetic MR imaging could serve as an alternative to conventional MR imaging in evaluating MS with a reduced scan time.

Changes of QT interval in the acute phase after pulmonary vein isolation for paroxysmal atrial fibrillation

Introduction

Pulmonary vein isolation (PVI) affects ganglionated plexi (GP) around the atrium, leading to a modification of the intrinsic cardiac autonomic system (ANS). In animal models, GP ablation has a potential risk of QT prolongation and ventricular arrhythmias. However, the impact of PVI on QT intervals in humans remains unclear.

Purpose

This study aims to evaluate the Impact of PVI on QT interval in patients with paroxysmal atrial fibrillation.

Methods

We analyzed consecutive 117 PAF patients for their first PVI procedures. 12-lead ECG was evaluated at baseline, 4 hr, day 1, 1 month, and 3 months after ablation. Only patients with sinus rhythm on 12-lead ECG at each evaluation point without antiarrhythmic drugs were included.

Results

Heart rate significantly increased at 4 hr, day 1, and 1 month. Raw QT interval prolonged at 4 hr (417.1±41.6 ms, P&lt;0.001) but shortened at day 1 (376.4±34.1 ms, P&lt;0.001), 1 month (382.2±31.5 ms, P&lt;0.001), and 3 months (385.1±32.8 ms, P&lt;0.001) compared to baseline (391.6±31.4 ms). Bazett- and Fridericia- corrected QTc intervals significantly prolonged at 4hr (Bazett: 430.8±27.9 ms, P&lt;0.001; Fridericia: 425.8±27.4 ms, P&lt;0.001), day1 (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 414.1±23.7 ms, P&lt;0.001), 1M (Bazett: 434.8±22.3 ms, P&lt;0.001; Fridericia: 408.2±21.0 ms, P&lt;0.05), and 3M (Bazett: 420.1±21.8 ms, P&lt;0.001; Fridericia: 407.8±21.1 ms, P&lt;0.05) compared to baseline (Bazett: 404.9±25.2 ms; Fridericia: 400.0±22.6 ms). On the other hand, Framingham- and Hodges- corrected QTc interval significantly prolonged only at 4hr (Framingham: 424.1±26.6 ms, P&lt;0.001; Hodges: 426.8±28.4 ms, P&lt;0.001) and at day1 (Framingham: 412.3±29.3 ms, P&lt;0.01; Hodges: 410.6±40.2 ms, P&lt;0.05) compared to baseline (Framingham: 399.2±22.7 ms; Hodges: 400.7±22.8 ms). At 4 hr after ablation, raw QT and QTc of all formulas significantly prolonged than baseline. Raw QT and QTc prolongation at 4hr after ablation were more frequently observed in female patients. Multiple regression analysis revealed that female patient is a significant predictor of raw QT and QTc interval prolongation of all formulas 4hr after PVI.

Conclusions

Raw QT and QTc prolonged after PVI, especially in the acute phase. Female patient is a risk factor for QT prolongation in the acute phase after PVI.

Funding Acknowledgement

Type of funding source: None

Prioritization of patient safety health policies: Delphi survey using patient safety experts in Japan

Various patient safety interventions have been implemented since the late 1990s, but their evaluation has been lacking. To obtain basic information for prioritizing patient safety interventions, this study aimed to extract high-priority interventions in Japan and to identify the factors that influence the setting of priority. Six perspectives (contribution, dissemination, impact, cost, urgency, and priority) on 42 patient safety interventions classified into 3 levels (system, organizational, and clinical) were evaluated by Japanese experts using the Delphi technique. We examined the relationships of the levels and the perspectives on interventions with the transition of the consensus state in rounds 1 and 3. After extracting the high-priority interventions, a chi-squared test was used to examine the relationship of the levels and the impact/cost ratio with high priority. Regression models were used to examine the influence of each perspective on priority. There was a significant relationship between the level of interventions and the transition of the consensus state (p = 0.033). System-level interventions had a low probability of achieving consensus. “Human resources interventions,” “professional education and training,” “medication management/reconciliation protocols,” “pay-for performance (P4P) schemes and financing for safety,” “digital technology solutions to improve safety,” and “hand hygiene initiatives” were extracted as high-priority interventions. The level and the impact/cost ratio of interventions had no significant relationships with high priority. In the regression model, dissemination and impact had an influence on priority (β = -0.628 and 0.941, respectively; adjusted R-squared = 0.646). The influence of impact and dissemination on the priority of interventions suggests that it is important to examine the dissemination degree and impact of interventions in each country for prioritizing interventions.

AB1137 CLASSIFICATION OF THE EARLY STAGE OF RAPIDLY DESTRUCTIVE COXOPATHY ACCORDING TO THE FEMORAL HEAD DESTRUCTION

Background:

Rapidly destructive coxopathy (RDC) is an unusual subset of osteoarthritis of the hip characterized by rapid chondrolysis with progressive loss of the joint space as the first manifestation of the disease. Because rapid progression of RDC makes it difficult to obtain sequential radiographs in its early stage, the process of disease progression in the early stage remains unclear. Although the pathogenesis of RDC is still unclarified, the potential causes of RDC include subchondral insufficiency fracture of the femoral head resulting from osteoporosis, pelvic posterior inclination in RDC as a mechanical factor, and increased serum levels of matrix metalloproteinase (MMP)-3 as a biological factor.

Objectives:

This study aimed to differentiate the process of disease progression in the early stage of RDC and provide its new classification system.

Methods:

This monocentric retrospective study included 42 female patients who met the criteria of RPOH, chondrolysis >2 mm during 12 months from the onset of hip pain based on a series of radiographs and computed tomography (CT). This study also included 9 female patients with osteoarthritis secondary to developmental dysplasia of the hip (DDH), who demonstrated chondrolysis >2 mm during 12 months from the onset of hip pain. Cortical thickness index (CTI) correlated with bone mineral density of the hip, pelvic tilt, and serum concentrations of matrix metalloproteinase (MMP)-3 were analyzed.

Results:

RDC were classified into two types based on the absence (type 1, n=17) and presence (type 2, n=25) of subsequent femoral head destruction shown by CT within 12 months after the onset of hip pain. MMP-3 significantly increased in RDC type 2 compared with type 1 and DDH. Increased posterior pelvic tilt was found in RDC type 2 compared with DDH. Logistic regression and receiver operating characteristic curve analyses indicated that MMP-3 may be associated with differentiation between RDC types 1 and 2. No difference was found in CTI between RDC types and DDH.

RDC type 2 hips developed partial (type 2A) and massive (type 2B) femoral head destruction within the first 12 months. Whereas partial destruction showed <20% collapse ratio, massive destruction demonstrated >40% collapse ratio. Increased posterior pelvic tilt was found in massive destruction. Femoral head destruction started earlier within the first 6 months in massive destruction compared with that in partial destruction. From receiver operating characteristic curve analysis, pelvic tilt differentiated the femoral head destruction types using the initial radiograph at the onset before first demonstration of femoral head destruction. No difference was found in CTI or MMP-3 between the two subtypes.

Conclusion:

Disease progression of RDC during 12 months after the onset of hip pain could be classified into two distinct types based on the absence (type 1) and presence (type 2) of femoral head destruction in association with MMP-3 and pelvic tilt as biological and mechanical factors, respectively. MMP-3 may be helpful to differentiate those two types in the early stage of RPOH. The extent of femoral head destruction could further differentiate RDC type 2 into two subtypes based on pelvic tilt.

Acknowledgments :

This study was supported by the Japan Hip Joint Foundation.

Disclosure of Interests:

None declared

Trends in hospital standardized mortality ratios for stroke in Japan between 2012 and 2016: a retrospective observational study

OBJECTIVE

Stroke is one of the leading causes of death and disability, and imposes a major healthcare burden. The aim of this study was to determine the characteristics of hospital standardized mortality ratios (HSMRs) for stroke in Japan for the year 2012-16 to describe the trend.

DESIGN

Retrospective observational study.

SETTING

Data from the Japanese administrative database.

PARTICIPANTS

All hospital admissions for stroke were identified from diagnostic procedures combination (DPC) database from 2012 to 2016.

MAIN OUTCOME MEASURES

HSMR was calculated using the actual number of in-hospital deaths and expected deaths. To obtain the expected death number, a logistic regression model was developed to get the coefficient with a number of explanatory variables. Predictive accuracy of the logistic models was assessed using c-index and calibration was evaluated using the Hosmer-Lemeshow test.

RESULTS

A total of 63 084 patients admitted for stroke from January 2012 to December 2016 were analyzed. HSMRs showed declining tendency over these 5 years, suggesting stroke-related mortality has been improving. While the HSMRs varied from year to year, a wide variation was also seen among the different hospitals in Japan. The proportion of hospitals with HSMR less than 100 increased from 41.0% in 2012 to 59.0% in 2016.

CONCLUSION

This study demonstrated that HSMR can be calculated using DPC data and found wide variation in HSMR of stroke among hospitals in Japan and enabled us to image the trend. By examining these trends, facilities, authorities and provinces can initiate designs that will ultimately lead to an upgraded healthcare delivery system.

Relationship of patient safety culture with factors influencing working environment such as working hours, the number of night shifts, and the number of days off among healthcare workers in Japan: a cross-sectional study

Background

Patient safety culture is defined as a product of individual and group values, attitudes, perceptions, competencies, and patterns of behavior that determine the commitment to, and the style and proficiency of, an organization’s health and safety management. Factors influencing healthcare workers’ working environment such as working hours, the number of night shifts, and the number of days off may be associated with patient safety culture, and the association pattern may differ by profession. This study aimed to examine the relationship between patient safety culture and working environment.

Methods

Questionnaire surveys were conducted in 2015 and 2016. The first survey was conducted in hospitals in Japan to investigate their patient safety management system and activities and intention to participate in the second survey. The second survey was conducted in 40 hospitals; 100 healthcare workers from each hospital answered a questionnaire that was the Japanese version of the Hospital Survey on Patient Safety Culture for measuring patient safety culture. The relationship of patient safety culture with working hours in a week, the number of night shifts in a month, and the number of days off in a month was analyzed.

Results

Response rates for the first and second surveys were 22.4% (731/3270) and 94.2% (3768/4000), respectively. Long working hours, numerous night shifts, and few days off were associated with low patient safety culture. Despite adjusting the working hours, the number of event reports increased with an increase in the number of night shifts. Physicians worked longer and had fewer days off than nurses. However, physicians had fewer composites of patient safety culture score related to working hours, the number of night shifts, and the number of days off than nurses.

Conclusions

This study suggested a possibility of improving the patient safety culture by managing the working environment of healthcare workers. High number of night shifts may lead to high number of event reports. Working hours, the number of night shifts, and the number of days off may differently influence patient safety culture in physicians and nurses.

Long-term follow-up of the randomized trial of mesorectal excision with or without lateral lymph node dissection in rectal cancer (JCOG0212)

BACKGROUND

Japan Clinical Oncology Group (JCOG) 0212 (ClinicalTrials.gov NCT00190541) was a non-inferiority phase III trial of patients with clinical stage II-III rectal cancer without lateral pelvic lymph node enlargement. The trial compared mesorectal excision (ME) with ME and lateral lymph node dissection (LLND), with a primary endpoint of recurrence-free survival (RFS). The planned primary analysis at 5 years failed to confirm the non-inferiority of ME alone compared with ME and LLND. The present study aimed to compare ME alone and ME with LLND using long-term follow-up data from JCOG0212.

METHODS

Patients with clinical stage II-III rectal cancer below the peritoneal reflection and no lateral pelvic lymph node enlargement were included in this study. After surgeons confirmed R0 resection by ME, patients were randomized to receive ME alone or ME with LLND. The primary endpoint was RFS.

RESULTS

A total of 701 patients from 33 institutions were assigned to ME with LLND (351) or ME alone (350) between June 2003 and August 2010. The 7-year RFS rate was 71.1 per cent for ME with LLND and 70·7 per cent for ME alone (hazard ratio (HR) 1·09, 95 per cent c.i. 0·84 to 1·42; non-inferiority P = 0·064). Subgroup analysis showed improved RFS among patients with clinical stage III disease who underwent ME with LLND compared with ME alone (HR 1·49, 1·02 to 2·17).

CONCLUSION

Long-term follow-up data did not support the non-inferiority of ME alone compared with ME and LLND. ME with LLND is recommended for patients with clinical stage III disease, whereas LLND could be omitted in those with clinical stage II tumours.

A two-way molecular dialogue between embryo and endosperm is required for seed development

The plant embryonic cuticle is a hydrophobic barrier deposited de novo by the embryo during seed development. At germination, it protects the seedling from water loss and is, thus, critical for survival. Embryonic cuticle formation is controlled by a signaling pathway involving the ABNORMAL LEAF SHAPE1 subtilase and the two GASSHO receptor-like kinases. We show that a sulfated peptide, TWISTED SEED1 (TWS1), acts as a GASSHO ligand. Cuticle surveillance depends on the action of the subtilase, which, unlike the TWS1 precursor and the GASSHO receptors, is not produced in the embryo but in the neighboring endosperm. Subtilase-mediated processing of the embryo-derived TWS1 precursor releases the active peptide, triggering GASSHO-dependent cuticle reinforcement in the embryo. Thus, a bidirectional molecular dialogue between embryo and endosperm safeguards cuticle integrity before germination.

Capturing the trends in hospital standardized mortality ratios for pneumonia: a retrospective observational study in Japan (2010 to 2018)

Background

Pneumonia has a high human toll and a substantial economic burden in developed countries like Japan, where the crude mortality rate was 77.7 per 100,000 people in 2017. As this trend is going to continue with increasing number of the elderly multi-morbid population in Japan; monitoring performance over time is a social need to alleviate the disease burden. The study objective was to determine the characteristics of hospital standardized mortality ratios (HSMRs) for pneumonia in Japan from 2010 to 2018 to describe this trend.

Methods

Data of the DPC (Diagnostic Procedures Combination) database were used, which is an administrative claims and discharge summary database for acute care in-patients in Japan. HSMRs were calculated using the actual and expected numbers of in-hospital deaths, the latter of which was calculated using logistic regression model, with a number of explanatory variables, e.g., age, sex, urgency of admission, mode of transportation, patient volume per month in each hospital, A-DROP score, and Charlson comorbidity index (CCI). We constructed two HSMR models: a single-year model, which included hospitals with > 10 in-patients per month and, a 9-year model, which included those hospitals with complete 9-year data. Predictive accuracy of the logistic models was assessed using c-index (area under receiver operating curve).

Results

Total 230,372 patients were included for the analysis over the 9-year study period. Calculated HSMRs showed wide variation among hospitals. The proportion of hospitals with HSMR less than 100 increased from 36.4% in 2010 to 60.6% in 2018. Both models showed good predictive ability with a c-statistic of 0.762 for the 9-year model, and no less than 0.717 for the single-year model.

Conclusion

This study denoted that HSMRs of pneumonia can be calculated using DPC data in Japan and revealed significant variations among hospitals with comparable case-mixes. Therefore, HSMR can be used as yet another measure to help improve quality of care over time if other indicators are examined in parallel and to get a clear picture of where hospitals excel and lack.

P1518 Relationship between post-operative asymptomatic status and reverse remodeling of large left atrium in patients with aortic stenosis who underwent aortic valve replacement

Introduction

Recently, we have reported that large left atrial volume (minimum left atrial volume index : LAVImin ≥30ml/m²) at end-diastole determined by direct exposure of left ventricular (LV) end-diastolic pressure can predict post-operative symptomatic status after aortic valve replacement (AVR) in aortic stenosis (AS) patients with high sensitivity and modest specificity. Reverse remodeling of large LAVImin after AVR may contribute to false positive for the prediction of post-operative symptomatic status in patients with AS.

Purpose

The purpose of this study was to evaluate relationship between post-operative symptomatic status and reverse remodeling of large LAVImin in patients with AS who underwent AVR.

Methods

The study population consisted of 75 patients with AS who underwent AVR and were followed up for 600 days after AVR, after the exclusion of the followings; atrial fibrillation, significant coronary artery disease, significant mitral valve disease, pacemaker rhythm, and inadequate echocardiographic images. We measured LAVImin by biplane Simpson"s method before and after AVR. Preoperative large LAVImin (≥30ml/m²) according to the previous study was observed in 32 (43%) of 75 patients. We divided these 32 patients into two groups according to the post-operative symptomatic status during the follow-up period.

Results

There was no significant difference in pre-operative LAVImin between patients with and without post-operative symptom (46.5 ± 13.4 vs 40.4 ± 8.6 ml/m²). On the other hand, post-operative LAVImin in patients without post-operative symptom was significantly smaller than that in patients with post-operative symptom (31.5 ± 8.6 vs 54.8 ± 14.0 ml/m², p &lt; 0.01). While significant regression in LAVImin after AVR was observed in patients without post-operative symptom (40.4 ± 8.6 to 31.5 ± 8.6 ml/m², p &lt; 0.05), no regression in LAVImin after AVR was observed in patients with post-operative symptom (46.5 ± 13.4 to 54.8 ± 14.0 ml/m²).

Conclusions

Reverse remodeling of large LAVmin in patients with AS who underwent AVR was observed in post-operative asymptomatic group, but not in symptomatic group. These results suggest that reverse remodeling of large LAVImin after AVR could contribute to the post-operative asymptomatic status in patients with AS who underwent AVR.

Patient safety management systems, activities and work environments related to hospital-level patient safety culture: A cross-sectional study

Improvement in patient safety culture requires constant attention. This study aimed to identify hospital-level elements related to patient safety culture, such as patient safety management systems, activities and work environments.Two questionnaire surveys were administered to hospitals in Japan in 2015 and 2016. The first survey aimed to determine which hospitals would allow their staff to respond to a questionnaire survey. The second survey aimed to measure the patient safety culture in those hospitals. Patient safety culture was assessed using the Hospital Survey on Patient Safety Culture (HSOPS). The relationship of hospital-level patient safety culture with the aforementioned elements in each hospital was analyzed.The response rate to the first survey was 22% (721/3270), and 40 eligible hospitals were selected from the respondents. The second survey was administered to healthcare workers in those 40 hospitals, and the response rate was 94% (3768/4000). The proportion of respondents who had 7 or more days off each month was related to the scores of 7 composites and the Patient Safety Grade of HSOPS. Both the presence of a mission statement describing patient safety and the proportion of respondents who participated in in-house patient safety workshops at least twice annually were related to the scores of 5 composites and the Patient Safety Grade of HSOPS.Our study suggests that the number of days off each month, the presence of a hospital patient safety mission statement, and the participation rate in in-house patient safety workshops might be key factors in creating a good patient safety culture within each hospital.

The structure of the quality of clinical practice guidelines with the items and overall assessment in AGREE II: a regression analysis

Background

The Appraisal of Guidelines for Research & Evaluation (AGREE) II has been widely used to evaluate the quality of clinical practice guidelines (CPGs). While the relationship between the overall assessment of CPGs and scores of six domains were reported in previous studies, the relationship between items constituting these domains and the overall assessment has not been analyzed. This study aims to investigate the relationship between the score of each item and the overall assessment and identify items that could influence the overall assessment.

Methods

All Japanese CPGs developed using the evidence-based medicine method and published from 2011 to 2015 were used. They were independently evaluated by three appraisers using AGREE II. The evaluation results were analyzed using regression analysis to evaluate the influence of 6 domains and 23 items on the overall assessment.

Results

A total of 206 CPGs were obtained. All domains and all items except one were significantly correlated to the overall assessment. Regression analysis revealed that Domain 3 (Rigour of Development), Domain 4 (Clarity of Presentation), Domain 5 (Applicability), and Domain 6 (Editorial Independence) had influence on the overall assessment. Additionally, four items of AGREE II, clear selection of evidence (Item 8), specific/unambiguous recommendations (Item 15), advice/tools for implementing recommendations (Item 19), and conflicts of interest (Item 22), significantly influenced the overall assessment and explained 72.1% of the variance.

Conclusions

These four items may highlight the areas for improvement in developing CPGs.

P2850Time to isolation guided hot balloon ablation for pulmonary vein isolation

Background

One disadvantage of hot balloon ablation (HBA) system is that real time monitoring of pulmonary vein (PV) potential is technically impossible. Therefore, the optimal radiofrequency-generated thermal energy application duration and application number are not completely established.

Purpose

The aim of this study is to evaluate the utility of 2Fr 4-electrode unidirectional catheter inserted into PV along with HB for real time monitoring of PV potential and investigate the time to isolation (TTI) guided optimal application strategy for HB based PV isolation in the acute phase.

Methods

We evaluated 23 consecutive patients who performed PV isolation using HBA system. Real time monitoring of PV potential was performed by 2Fr 4-electrode unidirectional catheter inserted into PV along with HB (Figure1A). After HBA applications, PV isolation was validated by high-resolution mapping with the 20-pole steerable mapping (PENTARAY) catheter as a standard. PV potentials during HBA application were categorized into five patterns. PV potentials disappeared during HBA applications and not emerged again (acute isolation), disappeared but verified by PENTARAY catheter (pseudo isolation), once disappeared but emerged again during the same application (acute reconnection), visible but not disappeared (ineffective application) and Invisible (Figure1B).

TTI, difference between TTI and time to reach target temperature (TTRT), balloon temperature at isolation and ablation time after isolation were examined for each applications.

Results

Out of 92 PVs, 69/92 (75.0%) PVs were isolated using HBA and 23/92 (25.0%) PVs required touch up ablation. In total, 120 applications were performed. Real time monitoring of the PV activity was obtained in 114 of 120 applications (95.0%). The distribution of PV potential patterns were 64/120 (53.3%), 2/120 (1.7%), 27/120 (22.5%), 23/120 (19.2%), for acute isolation, pseudo isolation, acute reconnection, ineffective application, respectively.

TTI and difference between TTI and TTRT were significantly shorter in the acute isolation group. Balloon temperature at isolation was significantly lower, TTRT and ablation time after isolation was significantly longer in the acute isolation group. Among them, TTI and difference between TTI and TTRT were highly predictive by receiver operation characteristics curve analysis. TTI <36.5s predicted successful application with sensitivity 83.9% and specificity 79.3%. Difference between TTI and TTRT <6.5s predicted with sensitivity 82.3% and specificity 89.7%.

Figure 1

Conclusions

In HBA system, real time monitoring of PV potentials can be obtained using 2Fr 4-electrode unidirectional catheter and accuracy to confirm an ostial PV isolation is relatively high.

TTI <36.5s and difference between TTI and TTRT <6.5s could be a suitable target for effective application.

P5636Lipid core burden index is associated with microcirculatory dysfunction even in stable angina pectoris; Insights from intracoronary electrocardiography

Background

Combined near-infrared spectroscopy (NIRS) and intravascular ultrasonography (NIRS-IVSU) is an imaging modality for precise detection of lipid core burden. Distal embolization has been reported to be a mechanism of microcirculatory dysfunction (MD) caused by percutaneous coronary intervention (PCI). High lipid core burden index at the 4-mm maximal segment (max-LCBI(4)) has been associated with the cardiovascular event. A max-LCBI(4) of >500 was related to perioperative myocardial infarction even in patients with stable angina pectoris. Unlike 12-lead electrocardiography, intracoronary electrocardiography can detect slight ischemia during PCI, maybe indicating distal embolization. However, whether PCI for culprit plaques with a low max-LCBI(4) can cause MD is unclear. Thus, this study aimed to investigate whether plaques with low max-LCBI(4) influence MD, using intracoronary electrocardiography.

Methods

Forty consecutive patients who underwent PCI for stable angina pectoris due to stenosis of the proximal segment of the left anterior descending artery were enrolled. NIRS-IVUS was performed in all the patients before predilatation to evaluate for the culprit lesion. Total LCBI and max-LCBI(4) within the culprit lesion were measured. On gray-scale IVUS, vessel area, lumen area, plaque volume, and percent (%) plaque volume were measured. Intracoronary electrography was performed at stent implantation to measure the time from the initiation of S-T segment elevation from the isoelectric baseline to the return of S-T segment to the isoelectric baseline after the deflation of the stent balloon, which was defined as the severity of the MD. The patients were divided into 2 groups according to median max-LCBI(4) (high [n=20] and low LCBI groups [n=20]).

Results

The mean age was 72±6 years. Of the patients, 80% were male. The mean overall max-LCBI(4) was 140±100. Max-LCBI(4) was significantly higher in the high-LCBI(4) group than in the low-LCBI(4) group. No significant differences in age, body mass index, American College of Cardiology and American Heart Association classification, and low-density lipoprotein level were found between the groups, as well as in the gray-scale IVUS parameters such as %plaque volume. The mean time from the initiation of the initiation of S-T segment elevation from the isoelectric baseline to the return of S-T segment to the isoelectric baseline was significantly longer in the high LCBI group than in the low LCBI group (33 vs 12 sec, P=0.01) despite no change in the S-T segment on 12-lead electrography. The S-T segment elevation occurred only during stent balloon inflation and returned to the isoelectric baseline immediately after stent balloon deflation at a max-LCBI(4) of 0. The no-reflow and slow flow phenomena were not observed.

Conclusion

Even low max-LCBI(4) on NIRS-IVUS was associated with MD during PCI in patients with stable angina pectoris.

P6257Low systolic blood pressure on admission as a predictor of outcome in octogenarian patients with heart failure and preserved ejection fraction

Background

Heart failure (HF) is an epidemic in healthcare worldwide including Asia. It appears that HF will become more serious with aging of the population. The patients with heart failure and preserved ejection fraction (HFpEF) were older, more often female, and frequently have comorbidities including hypertension. However, lower systolic blood pressure (SBP) on admission is associated with poor outcomes in patients with HF. It remains unclear whether this association is similar in very elderly patients with HFpEF.

Purpose

To investigate clinical features and prognosis in octogenarian HFpEF subjects.

Methods

We analyzed 87 consecutive subjects aged 80 years or older who were hospitalized for acute decompensated HF with left ventricular ejection fraction (LVEF) ≥50% between 2015 and 2017. Clinical characteristics and a composite event of cardiac death and HF hospitalization were compared in two groups according to SBP cut-off of 140 mmHg on admission.

Results

The prevalence of lower SBP subjects (mean BP = 118 mmHg) and higher SBP (mean BP = 166 mmHg) subjects were 41.4% and 58.6%, respectively. Lower SBP subjects were more comorbid with atrial fibrillation (72.2 vs. 45.1%, p=0.01). In the lower SBP group, diuretics, mineralocorticoid receptor antagonists (MRA), beta-blockers and ACE inhibitors/ARBs were more commonly used than higher SBP group (Table). During the observational period (median = 1.0 year), lower SBP on admission was associated with a 2.65-fold [95% confidence interval (CI): 1.29–5.55, p=0.009] greater likelihood of experiencing the composite events of cardiac death and rehospitalization for HF (Figure). This observation was still consistent even after adjusting clinical demographics and comorbidity [hazard ratio = 2.95, 95% CI: 1.30–6.87, p=0.01].

Table 1 Lower SBP group (n=36) Higher SBP group (n=51) P-value Atrial fibrillation (%) 72.2 0.01 0.01 Loop diuretic (%) 97.1 83.7 0.08 MRA (%) 47.1 24.5 0.04 Beta-blocker (%) 52.9 44.9 0.51 ACE inhibitor/ARB (%) 59.2 29.4 0.01

Figure 1

Conclusions

In octogenarian patients with acute decompensated HF and preserved LVEF, SBP on admission less than 140 mmHg is significantly associated with poor outcomes. Future studies need to prospectively evaluate optimal SBP treatment goals in very elderly patients with HFpEF.

White Matter Abnormalities in Multiple Sclerosis Evaluated by Quantitative Synthetic MRI, Diffusion Tensor Imaging, and Neurite Orientation Dispersion and Density Imaging

BACKGROUND AND PURPOSE

A number of MR-derived quantitative metrics have been suggested to assess the pathophysiology of MS, but the reports about combined analyses of these metrics are scarce. Our aim was to assess the spatial distribution of parameters for white matter myelin and axon integrity in patients with relapsing-remitting MS by multiparametric MR imaging.

MATERIALS AND METHODS

Twenty-four patients with relapsing-remitting MS and 24 age- and sex-matched controls were prospectively scanned by quantitative synthetic and 2-shell diffusion MR imaging. Synthetic MR imaging data were used to retrieve relaxometry parameters (R1 and R2 relaxation rates and proton density) and myelin volume fraction. Diffusion tensor metrics (fractional anisotropy and mean, axial, and radial diffusivity) and neurite orientation and dispersion index metrics (intracellular volume fraction, isotropic volume fraction, and orientation dispersion index) were retrieved from diffusion MR imaging data. These data were analyzed using Tract-Based Spatial Statistics.

RESULTS

Patients with MS showed significantly lower fractional anisotropy and myelin volume fraction and higher isotropic volume fraction in widespread white matter areas. Areas with different isotropic volume fractions were included within areas with lower fractional anisotropy. Myelin volume fraction showed no significant difference in some areas with significantly decreased fractional anisotropy in MS, including in the genu of the corpus callosum and bilateral anterior corona radiata, whereas myelin volume fraction was significantly decreased in some areas where fractional anisotropy showed no significant difference, including the bilateral posterior limb of the internal capsule, external capsule, sagittal striatum, fornix, and uncinate fasciculus.

CONCLUSIONS

We found differences in spatial distribution of abnormality in fractional anisotropy, isotropic volume fraction, and myelin volume fraction distribution in MS, which might be useful for characterizing white matter in patients with MS.

Quality assessment of clinical practice guidelines using the AGREE instrument in Japan: A time trend analysis

Background

Clinical practice guidelines (CPGs) are representative methods for promoting the standardization of healthcare and improvement of its quality. Few studies have investigated changes in the quality of CPGs published in a country over time. Our aim was to investigate changes in the quality of CPGs over time in the context of the available infrastructure for CPG development, public interest in healthcare quality, and healthcare providers’ responses to this interest.

Methods

All CPGs pertaining to evidence-based medicine (EBM) issued between 2000 and 2014 in Japan (n = 373) were evaluated using the Japanese version of the Appraisal of Guidelines for Research and Evaluation (AGREE) I. Additionally, time trends in quality were analyzed. Using a cut-off point based on the publication year of CPG development literature, the evaluated CPGs were classified into those published until 2008 (pre-2008) and those published since 2009 (post-2008). Subsequently, we compared these groups in terms of 1) first edition CPGs and its second editions, and 2) patients’ version of CPGs.

Results

Scores on all six domains of AGREE I improved each year. A comparison of the first- and second-edition of CPGs (n = 64) showed that scores on all domains improved significantly after revision. Significant improvement was observed in three domains (#2 stakeholder involvement, #3 rigor of development, and #4 clarity of presentation) in the pre-2008 group and in all domains in the post-2008 group. The comparison between the pre- and post-2008 groups in terms of CPGs for patients showed that the score increased in only one domain (#1 scope and purpose).

Conclusions

The number of published CPGs has been increasing and the quality of CPGs, as assessed using the AGREE I instrument, has been improving. These changes seem to be influenced by improvements in social infrastructure, such as the publication of CPG development procedures, availability of CPG preparation methodology training, and increase in CPG-related skills.

Improving the Quality of Synthetic FLAIR Images with Deep Learning Using a Conditional Generative Adversarial Network for Pixel-by-Pixel Image Translation

BACKGROUND AND PURPOSE

Synthetic FLAIR images are of lower quality than conventional FLAIR images. Here, we aimed to improve the synthetic FLAIR image quality using deep learning with pixel-by-pixel translation through conditional generative adversarial network training.

MATERIALS AND METHODS

Forty patients with MS were prospectively included and scanned (3T) to acquire synthetic MR imaging and conventional FLAIR images. Synthetic FLAIR images were created with the SyMRI software. Acquired data were divided into 30 training and 10 test datasets. A conditional generative adversarial network was trained to generate improved FLAIR images from raw synthetic MR imaging data using conventional FLAIR images as targets. The peak signal-to-noise ratio, normalized root mean square error, and the Dice index of MS lesion maps were calculated for synthetic and deep learning FLAIR images against conventional FLAIR images, respectively. Lesion conspicuity and the existence of artifacts were visually assessed.

RESULTS

The peak signal-to-noise ratio and normalized root mean square error were significantly higher and lower, respectively, in generated-versus-synthetic FLAIR images in aggregate intracranial tissues and all tissue segments (all P < .001). The Dice index of lesion maps and visual lesion conspicuity were comparable between generated and synthetic FLAIR images (P = 1 and .59, respectively). Generated FLAIR images showed fewer granular artifacts (P = .003) and swelling artifacts (in all cases) than synthetic FLAIR images.

CONCLUSIONS

Using deep learning, we improved the synthetic FLAIR image quality by generating FLAIR images that have contrast closer to that of conventional FLAIR images and fewer granular and swelling artifacts, while preserving the lesion contrast.

Medication-related osteonecrosis of the jaw after tooth extraction in cancer patients: a multicenter retrospective study

Root amputation, immunosuppressive therapy, mandibular tooth extraction, pre-existing inflammation, and longer duration of treatment with bone-modifying agents were significantly associated with an increased risk of medication-related osteonecrosis of the jaw. Hopeless teeth should be extracted without drug holiday before the development of inflammation in cancer patients receiving high-dose bone-modifying agents.

INTRODUCTION

No studies have comprehensively analyzed the influence of pre-existing inflammation, surgical procedure-related factors such as primary wound closure, demographic factors, and drug holiday on the incidence of medication-related osteonecrosis of the jaw (MRONJ). The purpose of this study was to retrospectively investigate the relationships between these various factors and the development of MRONJ after tooth extraction in cancer patients receiving high-dose bone-modifying agents (BMAs) such as bisphosphonates or denosumab.

METHODS

Risk factors for MRONJ after tooth extraction were evaluated with univariate and multivariate analyses. The following parameters were investigated in all patients: demographics, type and duration of BMA use, whether BMA use was discontinued before tooth extraction (drug holiday), the duration of such discontinuation, the presence of pre-existing inflammation, and whether additional surgical procedures (e.g., incision, removal of bone edges, root amputation) were performed.

RESULTS

We found that root amputation (OR = 22.62), immunosuppressive therapy (OR = 16.61), extraction of mandibular teeth (OR = 12.14), extraction of teeth with pre-existing inflammation, and longer duration (≥ 8 months) of high-dose BMA (OR = 7.85) were all significantly associated with MRONJ.

CONCLUSIONS

Tooth extraction should not necessarily be postponed in cancer patients receiving high-dose BMA. The effectiveness of a short-term drug holiday was not confirmed, as drug holidays had no significant impact on MRONJ incidence. Tooth extraction may be acceptable during high-dose BMA therapy until 8 months after initiation.

Cost of illness of leukemia in Japan - Trend analysis and future projections

BACKGROUND

Leukemia is a deadly hematological malignancy that usually affects all age groups and imposes significant burden on public funds and society. The objective of this study was to analyze the cost of illness (COI) of leukemia, and to mark out the underlying driving factors, in Japan.

METHODS

COI method was applied to the data from government statistics. We first summed up the direct and indirect costs from 1996 to 2014; then future COI for the year 2017-2029 was projected.

RESULTS

Calculated COI showed an upward trend with a 13% increase from 1996 to 2014 (270-305 billion yen). Increased COI was attributed to an increase in direct costs. Although mortality cost accounted for the largest proportion of COI, but followed a downward trend. Decreased mortality costs reflected the effects of aging. Mortality cost per person also decreased, however, the percentage of mortality cost for individuals ≥65 years of age increased consistently from 1996 to 2014. If a similar trend in health-related indicators continue, COI would remain stable from 2017 to 2029 regardless of models.

CONCLUSION

COI of leukemia increased from 1996 to 2014, but was projected to decrease in foreseeable future. With advancement of new therapies, leukemia has become potentially curable and require long-term care; so direct cost and morbidity cost will remain unchanged. This reveal the further continuing burden on public funds. Thus, the information obtained from this study can be regarded as beneficial to future policy making with respect to government policies in Japan.

Differential Inhibition of Fibrinogen Binding to Agonist-and RGDS Peptide-activated States of GPIIb-IIIa by an anti-GPIIIa Monoclonal Antibody, PMA5

Platelet agonists and RGD-containing peptides can convert platelet membrane glycoprotein (GP) Ilb-IIIa from its resting state to an activated state competent to bind soluble fibrinogen. We examined the effects of two anti-GPIIb-IIIa monoclonal antibodies, PMA1 and PMA5, on fibrinogen binding to agonist- and RGD-activated GPIIb-IIIa. PMA1 abolished aggregation of both agonist- and RGDS peptide-activated fixed platelets, and inhibited the binding of 125I-fibrinogen to these platelets almost completely. PMA5 had the same effects on agonist-activated platelets, but had little effect on the aggregation of RGDS-activated fixed platelets, and inhibited fibrinogen binding to RGDS-activated fixed platelets by only 44%. PMA5 bound to agonist- and RGDS-activated platelets equally. Immunoblot analysis showed that PMA5 bound to intact GPIIIa, but not to a 66 kDa fragment of GPIIIa digested by chymotrypsin. Although PMA5 inhibited platelet adhesion to immobilized fibrinogen by 94%, 44% of the remaining adherent platelets were spread. In contrast, no platelet spreading was observed in the presence of PMA1. These findings indicate that PMA5 is a novel anti-GPIIIa monoclonal antibody with the ability to inhibit fibrinogen binding to agonist- and RGD-activated states of GPIIb-IIIa differentially, and suggest that binding of immobilized fibrinogen to RGD-activated GPIIb-IIIa is necessary for platelet spreading.

Detection of Platelet Adhesion/Aggregation to Immobilized Ligands on Microbeads by an Aggregometer

Platelet aggregation is believed to follow platelet adhesion to vascular injury sites. We have developed a turbidimetric assay for platelet aggregation following platelet adhesion to immobilized ligands using an aggregometer. The addition of polystyrene beads coated with von Willebrand factor (vWF) or fibrinogen (Fg) to platelet suspensions caused prompt aggregation of beads and platelets, which was detected as an increase in light transmission. Electron microscopic analysis revealed that platelets adhered to the bead surfaces and that additional platelets adhered to already adhering platelets, leading to the formation of platelet aggregates. vWF-coated beads induced larger aggregates than Fg-coated beads. The interaction of vWF-coated beads with platelets was abolished by both GPIb and GPIIb-IIIa blockers, while that of Fg-coated beads was abolished by GPIIb-IIIa blockers. vWF-coated beads induced modest secretion of granules from platelets but no thromboxane B2 synthesis. Fg-coated beads induced neither reaction. However, pleckstrin phosphorylation and protein tyrosine phosphorylation was induced by both types of bead. Platelet aggregation following platelet adhesion to both types of bead was inhibited by ADP scavengers, a protein kinase C inhibitor and a tyrosine kinase inhibitor, but not by aspirin. These findings suggest that vWF- and Fg-coated beads can induce platelet aggregation following platelet adhesion through specific ligand-receptor interactions and intracellular signaling. Our simple assay using these beads may represent a useful test for immobilized ligand-induced platelet adhesion and aggregation.