The combination of hydrogen gas and hydrogen-rich solution does not protect against ischemic spinal cord injury in rabbits

PURPOSE

This study aimed to determine whether the combination of H2 gas inhalation and administration of hydrogen-rich acetated Ringer's solution (HS) could protect against ischemic spinal cord injury in rabbits.

METHODS

In Experiment 1, rabbits were randomly assigned to a 1.2% H2 gas group, HS group, 1.2% H2 gas + HS group (combination group), or control group (n = 6 per group). The H2 concentration of HS was 0.65 mM. H2 was inhaled for 60 min, starting 5 min before reperfusion. HS (20 mL/kg) was divided into six bolus injections at 10-min intervals, starting 5 min before reperfusion. Spinal cord ischemia was produced by occluding the abdominal aorta for 15 min. Neurologic and histopathologic evaluations were performed 7 days after reperfusion. In Experiment 2, H2 concentrations in spinal cord tissue according to the administration of 1.2% H2 gas or HS were compared by measuring the electric current through a platinum needle electrode (n = 2). In Experiment 3, rabbits were assigned to a 2% H2 gas group or control group (n = 6 per group). Spinal cord ischemia was produced and neurologic and histopathologic evaluations were performed as in Experiment 1.

RESULTS

There were no significant differences among the groups in the neurologic and histopathologic outcomes in Experiments 1 and 3. Bolus administration of HS (10 mL) transiently increased the current to only 1/30th and 1/27th of the plateau current with 1.2% H2 gas inhalation in two animals.

CONCLUSION

These results suggest that the combination of 1.2% H2 gas inhalation and administration of a hydrogen-rich solution does not protect against ischemic spinal cord injury and that the increase in H2 concentration in spinal cord tissue after administration of HS is very low compared to 1.2% H2 gas inhalation.

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

BACKGROUND

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

METHODS

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

FINDINGS

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

INTERPRETATION

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

FUNDING

Boehringer Ingelheim and Eli Lilly.

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

BACKGROUND

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

METHODS

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

FINDINGS

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

INTERPRETATION

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

FUNDING

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

Inhibition of Mertk Signaling Enhances Bone Healing after Tooth Extraction

Regeneration of alveolar bone is an essential step in restoring healthy function following tooth extraction. Growth of new bone in the healing extraction socket can be variable and often unpredictable when systemic comorbidities are present, leading to the need for additional therapeutic targets to accelerate the regenerative process. One such target is the TAM family (Tyro3, Axl, Mertk) of receptor tyrosine kinases. These proteins have been shown to help resolve inflammation and maintain bone homeostasis and thus may have therapeutic benefits in bone regeneration following extraction. Treatment of mice with a pan-TAM inhibitor (RXDX-106) led to accelerated alveolar bone fill following first molar extraction in a mouse model without changing immune infiltrate. Treatment of human alveolar bone mesenchymal stem cells with RXDX-106 upregulated Wnt signaling and primed the cells for osteogenic differentiation. Differentiation of human alveolar bone mesenchymal stem cells with osteogenic media and TAM-targeted inhibitor RXDX-106 (pan-TAM), ASP-2215 (Axl specific), or MRX-2843 (Mertk specific) showed enhanced mineralization with pan-TAM or Mertk-specific inhibitors and no change with Axl-specific inhibitor. First molar extractions in Mertk-/- mice had increased alveolar bone regeneration in the extraction socket relative to wild type controls 7 d postextraction. Flow cytometry of 7-d extraction sockets showed no difference in immune cell numbers between Mertk-/- and wild type mice. RNAseq of day 7 extraction sockets showed increased innate immune-related pathways and genes associated with bone differentiation in Mertk-/- mice. Together, these results indicate that TAM receptor signaling, specifically through Mertk, can be targeted to enhance bone regeneration after injury.

Effect of cerebrospinal fluid drainage pressure in descending and thoracoabdominal aortic repair: a prospective multicenter observational study

PURPOSE

Cerebrospinal fluid drainage (CSFD) is recommended during open or endovascular thoracic aortic repair. However, the incidence of CSFD complications is still high. Recently, CSF pressure has been kept high to avoid complications, but the efficacy of CSFD at higher pressures has not been confirmed. We hypothesize that CSFD at higher pressures is effective for preventing motor deficits.

METHODS

This prospective observational study included 14 hospitals that are members of the Japanese Society of Cardiovascular Anesthesiologists. Patients who underwent thoracic and thoracoabdominal aortic repair were divided into four groups: Group 1, CSF pressure around 10 mmHg; Group 2, CSF pressure around 15 mmHg; Group 3, CSFD initiated when motor evoked potential amplitudes decreased; and Group 4, no CSFD. We assessed the association between the CSFD group and motor deficits using mixed-effects logistic regression with a random intercept for the institution.

RESULTS

Of 1072 patients in the study, 84 patients (open surgery, 51; thoracic endovascular aortic repair, 33) had motor deficits at discharge. Groups 1 and 2 were not associated with motor deficits (Group 1, odds ratio (OR): 1.53, 95% confidence interval (95% CI): 0.71-3.29, p = 0.276; Group 2, OR: 1.73, 95% CI: 0.62-4.82) when compared with Group 4. Group 3 was significantly more prone to motor deficits than Group 4 (OR: 2.56, 95% CI: 1.27-5.17, p = 0.009).

CONCLUSION

CSFD is not associated with motor deficits in thoracic and thoracoabdominal aortic repair with CSF pressure around 10 or 15 mmHg.

Formation and evolution of carbonaceous asteroid Ryugu: Direct evidence from returned samples

Samples of the carbonaceous asteroid Ryugu were brought to Earth by the Hayabusa2 spacecraft. We analyzed 17 Ryugu samples measuring 1 to 8 millimeters. Carbon dioxide-bearing water inclusions are present within a pyrrhotite crystal, indicating that Ryugu's parent asteroid formed in the outer Solar System. The samples contain low abundances of materials that formed at high temperatures, such as chondrules and calcium- and aluminum-rich inclusions. The samples are rich in phyllosilicates and carbonates, which formed through aqueous alteration reactions at low temperature, high pH, and water/rock ratios of <1 (by mass). Less altered fragments contain olivine, pyroxene, amorphous silicates, calcite, and phosphide. Numerical simulations, based on the mineralogical and physical properties of the samples, indicate that Ryugu's parent body formed ~2 million years after the beginning of Solar System formation.

Early vascular responses to abluminal biodegradable polymer-coated versus circumferential durable polymer-coated newer-generation drug-eluting stents in humans: a pathologic study

Background

Recent clinical trials are testing strategies for short (1–3 months) dual antiplatelet therapy (DAPT) following newer-generation drug-eluting stent (DES) placement. However, the safety of short DAPT regimens is not supported by biological evidence in humans.

Purpose

We sought to evaluate early pathologic responses to newer-generation DES by comparing abluminal biodegradable polymer-coated DES (BP-DES) with circumferential durable polymer-coated DES (DP-DES) in human autopsy cases.

Methods

The study included a total of 37 coronary lesions with thin strut newer-generation DES (DP-DES=23 [XIENCE=18, Resolute Integrity=5] and BP-DES=14 [SYNERGY=9, Ultimaster=5]) with duration of implantation &lt;90 days in 25 autopsy cases. The process of stent healing was precisely evaluated for every single strut in association with underlying tissue characteristics. The degree of strut coverage was defined as follows: grade 0 (bare struts), grade 1 (struts covered with thrombus, fibrin, or other tissues or cells without endothelium), grade 2 (struts covered with single-layered endothelium without underlying smooth muscle cell layers), and grade 3 (struts covered with endothelium and underlying smooth muscle cell layers) (Figure 1).

Results

Duration of implantation was similar in lesions with DP-DES and those with BP-DES (median=20 vs. 17 days). A total of 1986 struts (DP-DES=1261, BP-DES=725) were pathologically analyzed. Focal grade 2 coverage was observed as early as 5 days after the implantation in both stents. Multilevel mixed-effects ordered logistic regression model demonstrated that BP-DES exhibited greater strut coverage compared with DP-DES (odds ratio; 3.50, 95% CI; 1.31–9.41, P=0.013), which remained significant after adjustment for duration of implantation and underlying tissue characteristics (odds ratio; 2.64, 95% CI; 1.04–6.68, P=0.040). The time course of vessel healing assessed as predictive probability of strut coverage (grade 0–3) stratified by duration of implantation is shown in Figure 2. Predictive probability of grade 2 and 3 coverage was comparably limited at 30 days (DP-DES=17.7% vs. BP-DES=29.0%) and increased at 90 days (DP-DES=76.1% vs. BP-DES=85.9%). Both stents showed few inflammation and similar degree of fibrin deposition.

Conclusions

The current first pathologic study on early biological responses to newer-generation DES in humans demonstrated that single-layered endothelial coverage begins in days following the stent placement, and abluminal BP-DES potentially exhibit faster strut coverage with smooth muscle cell infiltration than circumferential DP-DES. Nevertheless, vessel healing remains suboptimal at 30 days in both DP- and BP-DES, which progresses with time to become substantial at 90 days. Our results suggest that very short duration of DAPT for 1 month should be applied with caution, taking into account the trade-off between bleeding and thrombotic risks.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Grant-in-Aid for Scientific Research (C) from the Japan Society for the Promotion of Science

Increased levels of a pro-inflammatory IgG receptor in the midbrain of people with schizophrenia

BACKGROUND

There is growing evidence that neuroinflammation may contribute to schizophrenia neuropathology. Elevated pro-inflammatory cytokines are evident in the midbrain from schizophrenia subjects, findings that are driven by a subgroup of patients, characterised as a "high inflammation" biotype. Cytokines trigger the release of antibodies, of which immunoglobulin G (IgG) is the most common. The level and function of IgG is regulated by its transporter (FcGRT) and by pro-inflammatory IgG receptors (including FcGR3A) in balance with the anti-inflammatory IgG receptor FcGR2B. Testing whether abnormalities in IgG activity contribute to the neuroinflammatory abnormalities schizophrenia patients, particularly those with elevated cytokines, may help identify novel treatment targets.

METHODS

Post-mortem midbrain tissue from healthy controls and schizophrenia cases (n = 58 total) was used to determine the localisation and abundance of IgG and IgG transporters and receptors in the midbrain of healthy controls and schizophrenia patients. Protein levels of IgG and FcGRT were quantified using western blot, and gene transcript levels of FcGRT, FcGR3A and FcGR2B were assessed using qPCR. The distribution of IgG in the midbrain was assessed using immunohistochemistry and immunofluorescence. Results were compared between diagnostic (schizophrenia vs control) and inflammatory (high vs low inflammation) groups.

RESULTS

We found that IgG and FcGRT protein abundance (relative to β-actin) was unchanged in people with schizophrenia compared with controls irrespective of inflammatory subtype. In contrast, FcGRT and FcGR3A mRNA levels were elevated in the midbrain from "high inflammation" schizophrenia cases (FcGRT; p = 0.02, FcGR3A; p < 0.0001) in comparison to low-inflammation patients and healthy controls, while FcGR2B mRNA levels were unchanged. IgG immunoreactivity was evident in the midbrain, and approximately 24% of all individuals (control subjects and schizophrenia cases) showed diffusion of IgG from blood vessels into the brain. However, the intensity and distribution of IgG was comparable across schizophrenia cases and control subjects.

CONCLUSION

These findings suggest that an increase in the pro-inflammatory Fcγ receptor FcGR3A, rather than an overall increase in IgG levels, contribute to midbrain neuroinflammation in schizophrenia patients. However, more precise information about IgG-Fcγ receptor interactions is needed to determine their potential role in schizophrenia neuropathology.

New methods for determination of the keyhole position in the lateral suboccipital approach to avoid transverse-sigmoid sinus injury: Proposition of the groove line as a new surgical landmark

PURPOSE

The asterion is frequently used as an anatomical landmark to determine the location of a keyhole in the lateral suboccipital approach used in craniotomies. However, the asterion may not be ideal because of large individual differences among patients. We examined a simple and safe method for determining an optimal keyhole position (KP) using the digastric groove as a new landmark in the lateral suboccipital approach.

METHODS

Thirty-three patients with trigeminal neuralgia who underwent surgery in our institute between April 2014 and December 2018 were included. The groove line (GL) was designed accurately, extending the digastric groove on the surface of the occipital bone, as the x-axis. The y-axis was depicted from the posterior edge of the digastric groove (the groove point: GP) vertical to the GL. The x-y coordinates represented the distances from GP on each axis. The x-y coordinates of median edge of the transverse-sigmoid sinus (TSJ point), asterion, and the intersection of the GL and transverse sinus (the transverse point: TP) were investigated, based on intraoperative findings and recorded videos.

RESULTS

The x-y coordinated of the TSJ point were (23.9±3.9, 7.2±3.6). In all patients, the TSJ point was located superior to the GL. The x-y coordinates of the asterion were (27.3±6.0, 8.9±4.1), and in 28 of the 33 patients, their coordinates exceeded the TSJ points. The x-coordinate of the TP was 29.5±4.5, and was located behind the TSJ point on the GL in all patients. The shortest distance between the TSJ points and TP was approximately 3mm. According to these measurements, we decided that the optimal KP would be at 20mm from the GP, subjacent to the GL.

CONCLUSIONS

Our methods of using the GL as a new surgical landmark for setting the optimal KP is simple, safe, and useful.

Effects of Imprinting and Water Activity on Transesterification and Thermostability with Lipases in Ionic Liquid

The effect of bio-imprinting and water activity on catalytic activities and the thermostability of lipases was investigated for transesterification using vinyl acetate and benzyl alcohol as substrates in ionic liquid, [Cnmim][PF6] (n=4,6,8), and benzene. The catalytic activities were enhanced by imprinting in benzene and [C4mim][PF6], and the relations between the transesterification activities and the water activity in both solvents were approximately bell shaped. The reactivity of the transesterification in benzene was higher than that in [C4<br /> mim][PF6]. The effects of water activity and imprinting on the kinetic parameters in [C4mim][PF6] were examined. Without controlling the water content, the values of Km,VA and Km,BA (Michaelis constants of vinyl acetate and benzyl alcohol, respectively) decreased, and the values of Vm (maximum rate) increased by imprinting. On the other hand, by controlling the water content in the organic media, the values of Vm, Km,VA, and Km,BA increased by imprinting. The activities of lipase in ionic liquid are more strongly affected by water activity and imprinting than those in benzene. We observed effects of water activity on thermostability but none from imprinting.

Statins bring the prognostic impact only in peripheral artery disease patients with elevated c-reactive proteins -subanalysis from multicenter registry-

Introduction

Recent trials demonstrated favorable effects of statins on the clinical prognosis, partly through anti-inflammatory properties, in patients with coronary artery disease. However, this favorable effect has not been fully verified in patients with peripheral arterial disease (PAD). We hypothesized that statins exert different prognostic effects depending on the degrees of inflammation at the time of endovascular therapy (EVT).

Methods

This study is a subanalysis from the Toma-Code Registry that is a Japanese prospective cohort of 2,321 consecutive patients with PAD treated by endovascular therapy in hospitals from 2014 to 2016. After the exclusion of patients without information of C-reactive protein (CRP) at the time of index EVT, 2,039 patients including 1,039 statin users and 1,000 statin non-users were ultimately analyzed. The patient enrolled were divided into 4 categories depending on CRP level at the time of EVT; Low-CRP (&lt;0.1 mg/dL), Intermediate-low-CRP (0.1–0.3 mg/dL), Intermediate-High-CRP (0.3–1.0 mg/dL), and High-CRP (&gt;1.0 mg/dL). A composite of death, stroke, myocardial infarction, and major amputation as the primary endpoint of this study was compared between statin users and non-users in each CRP category.

Results

The composite endpoint occurred in 255 patients during the observation period. Overall, statin users had a significantly lower event rate than non-users (Log-rank test: P&lt;0.001). However, there were no significant difference in the event rates between statin users and non-users in the Low-, and Intermediate-Low-CRP categories. Only in the Intermediate-High- and the High-CRP categories, statin users showed a significantly lower event rates than non-users (P=0.02 and P=0.008, respectively, Figures). Additionally, multivariate Cox regression analysis in the High-CRP group revealed that statin use was independently associated with the primary endpoint (adjusted hazard ratio: 0.67 [95% confidence interval: 0.45–0.99]), even after the adjustment of covariants.

Conclusion

Statins may exert a favorable prognostic effect in PAD patients with highly elevated CRP, but not in those with low to moderate CRP level.

Event free survival

Funding Acknowledgement

Type of funding source: None

Transient ischemic attack without self-awareness of symptoms witnessed by bystanders: analysis of the PROMISE-TIA registry

Background and purpose

A transient ischemic attack (TIA) can occur without self‐awareness of symptoms. We aimed to investigate characteristics of patients with a tissue‐based diagnosis of TIA but having no self‐awareness of their symptoms and whose symptoms were witnessed by bystanders.

Methods

We used data from the multicenter registry of 1414 patients with a clinical diagnosis of TIA. For patients without evidence of ischemic lesions on imaging, clinical characteristics were compared between patients with and without self‐awareness of their TIA symptoms.

Results

Among 896 patients (559 men, median age of 70 years), 59 (6.6%) were unaware of their TIA symptoms, but had those symptoms witnessed by bystanders. Patients without self‐awareness of symptoms were older and more frequently female, and more likely to have previous history of stroke, premorbid disability, and atrial fibrillation, but less likely to have dyslipidemia than those with self‐awareness. Patients without self‐awareness of symptoms arrive at hospitals earlier than those with self‐awareness (P < 0.001). ABCD² score was higher in patients without self‐awareness of symptoms than those with self‐awareness (median 5 vs. 4, P = 0.002). Having no self‐awareness of symptoms was a significant predictor of ischemic stroke within 1 year after adjustment for sex, ABCD² score, and onset to arrival time (hazard ratio = 2.44, 95% confidential interval: 1.10–4.83), but was not significant after further adjustment for arterial stenosis or occlusion.

Conclusions

Patients with a TIA but having no self‐awareness of their symptoms might have higher risk of subsequent ischemic stroke rather than those with self‐awareness, suggesting urgent management is needed even if patients have no self‐awareness of symptoms.

Excessive dynamic airway collapse during general anesthesia: a case report

Background

Excessive dynamic airway collapse (EDAC) is an uncommon cause of high airway pressure during mechanical ventilation. However, EDAC is not widely recognized by anesthesiologists, and therefore, it is often misdiagnosed as asthma.

Case presentation

A 70-year-old woman with a history of asthma received anesthesia with sevoflurane for a laparotomic cholecystectomy. Under general anesthesia, she developed wheezing, high inspiratory pressure, and a shark-fin waveform on capnography, which was interpreted as an asthma attack. However, treatment with a bronchodilator was ineffective. Bronchoscopy revealed the collapse of the trachea and main bronchi upon expiration. We reviewed the preoperative computed tomography scan and saw bulging of the posterior membrane into the airway lumen, leading to a diagnosis of EDAC.

Conclusions

Although both EDAC and bronchospasm present as similar symptoms, the treatments are different. Bronchoscopy proved useful for distinguishing between these two entities. Positive end-expiratory pressure should be applied and bronchodilators avoided in EDAC.

Cerebrospinal fluid drainage to prevent postoperative spinal cord injury in thoracic aortic repair

BACKGROUND

Cerebrospinal fluid drainage (CSFD) is recommended as a spinal cord protective strategy in open and endovascular thoracic aortic repair. Although small studies support the use of CSFD, systematic reviews have not suggested definite conclusion and a large-scale study is needed. Therefore, we reviewed medical records of patients who had undergone descending and thoracoabdominal aortic repair (both open and endovascular repair) at multiple institutions to assess the association between CSFD and postoperative motor deficits.

METHODS

Patients included in this study underwent descending or thoracoabdominal aortic repair between 2000 and 2013 at 12 hospitals belonging to the Japanese Association of Spinal Cord Protection in Aortic Surgery. We conducted a retrospective study to investigate whether motor-evoked potential monitoring is effective in reducing motor deficits in thoracic aortic aneurysm repair. We use the same dataset to examine whether CSFD reduces motor deficits after propensity score matching.

RESULTS

We reviewed data from 1214 patients [open surgery, 601 (49.5%); endovascular repair, 613 (50.5%)]. CSFD was performed in 417 patients and not performed in the remaining 797 patients. Postoperative motor deficits were observed in 75 (6.2%) patients at discharge. After propensity score matching (n = 700), mixed-effects logistic regression performed revealed that CSFD is associated with postoperative motor deficits at discharge [adjusted odds ratio (OR), 3.87; 95% confidence interval (CI), 2.30-6.51].

CONCLUSION

CSFD may not be effective for postoperative motor deficits at discharge.

Clinically significant changes in pain along the Pain Intensity Numerical Rating Scale in patients with chronic low back pain

Low back pain (LBP) is the most common cause of chronic pain. Numerous clinical scales are available for evaluating pain, but their objective criteria in the management of LBP patients remain unclear. This study aimed to determine an objective cutoff value for a change in the Pain Intensity Numerical Rating Scale (ΔPI-NRS) three months after LBP treatment. Its utility was compared with changes in six commonly used clinical scales in LBP patients: Pain Disability Assessment Scale (PDAS), Pain Self-Efficacy Questionnaire (PSEC), Pain Catastrophizing Scale (PCS), Athens Insomnia Scale (AIS), EuroQoL 5 Dimension (EQ5D), and Locomo 25. We included 161 LBP patients treated in two representative pain management centers. Patients were partitioned into two groups based on patient’s global impression of change (PGIC) three months after treatment: satisfied (PGIC = 1, 2) and unsatisfied (3–7). Multivariate logistic regression analysis was performed to explore relevant scales in distinguishing the two groups. We found ΔPI-NRS to be most closely associated with PGIC status regardless of pre-treatment pain intensity, followed by ΔEQ5D, ΔPDAS, ΔPSEC, and ΔPCS. The ΔPI-NRS cutoff value for distinguishing the PGIC status was determined by ROC analysis to be 1.3–1.8 depending on pre-treatment PI-NRS, which was rounded up to ΔPI-NRS = 2 for general use. Spearman’s correlation coefficient revealed close relationships between ΔPI-NRS and the six other clinical scales. Therefore, we determined cutoff values of these scales in distinguishing the status of ΔPI-NRS≥2 vs. ΔPI-NRS<2 to be as follows: ΔPDAS, 6.71; ΔPSEC, 6.48; ΔPCS, 6.48; ΔAIS, 1.91; ΔEQ5D, 0.08; and ΔLocomo 25, 9.31. These can be used as definitive indicator of therapeutic outcome in the management of chronic LBP patients.

Enzymatic Kinetics of Solvent-free Esterification with Bio-imprinted Lipase

To avoid the use of compounds that burden the environment, a solvent-free enzymatic<br /> reaction was the focus of this study. Investigated were the catalytic activities and kinetics of lipases that were pretreated with carboxylic acids for the solvent-free esterification of propionic acid with isoamyl alcohol. The enhancements of the esterification yields and rates by the bio-imprinting effects of carboxylic acids were observed. We found no inhibition of isoamyl alcohol on the solvent-free enzymatic esterification, and obtained a large imprinting effect under a largely excessive amount of isoamyl alcohol to propionic acid. From the kinetic analysis, the imprinting of lipases mainly enhanced the catalytic reaction rate constant rather than the affinity between lipase and propionic acid compared with untreated lipase. The bio-imprinting treatment of lipase is found to be very effective for the yield and kinetics in solvent-free esterification.

Influence of the trapeziometacarpal joint fusion on thumb muscles and thumb-tip movement: A cadaveric study

BACKGROUND

Trapeziometacarpal (TMC) arthrodesis provides stability and strength of the thumb, whereas fixation of the TMC joint restricts motion of the thumb, which may consequently impair the activity of daily living. The objective of our study was to investigate how length and area of the thumb-tip trajectory were reduced after the TMC joint fusion.

METHODS

Six fresh, frozen cadavers were used for this study. Tension was applied to the distal tendons of 4 extrinsic thumb muscles (extensor pollicis longus, flexor pollicis longus, abductor pollicis longus, and extensor pollicis brevis) by servomotor, whereas tension was applied to 4 intrinsic muscles (abductor pollicis brevis, opponens pollicis, flexor pollicis brevis, and adductor pollicis) using static weights. The thumb-tip trajectory was examined using a motion capture system without tension and with 5 different weights to induce intrinsic muscle tension before and after the TMC joint fusion.

FINDINGS

When tension was applied to the intrinsic muscles, the length of the thumb-tip trajectory decreased in all conditions compared with that before the TMC joint fusion, whereas the trajectory decreased only when the abductor pollicis longus was pulled. The overall thumb-tip trajectory area was reduced to approximately 30% compared with that before the TMC joint fusion.

INTERPRETATION

Thumb-tip trajectory was restricted by the TMC joint fusion to approximately 30%. However, the reduced area was found tolerable for performing daily activities. Thus, arthrodesis can be the first-line treatment in patients who wish to engage in activities of daily living without difficulties.

Abstract P3-03-35: Prevalence and risk factors associated with development of lymphedema after axillary lymph node dissection among breast cancer patients: Single center retrospective study

Background: Lymphedema in breast cancer is one of the most important complications, and causes symptoms of arm swelling, heaviness and limited movement. Once lymphedema has occurred, it is difficult to cure. Nowadays, treatment with axillary lymph node dissection (ALND) has been decreasing among breast cancer patients as a result of the ACOSOG Z0011, AMAROS and IBCSG 23-01 trials. However, some cases require ALND for ALN metastasis. ALND increases the risk of lymphedema and detracts from quality of life, but the surgical procedure based on anatomical landmarks has not been changed for several decades. The upper borderline for ALND might cause injury to lymph ducts from arms, and incidence and risk factors for lymphedema after ALND are still unclear. Our aim was to identify prevalence and risk factors associated with development of lymphedema after ALND among breast cancer patients.

Methods: This retrospective study was based on data collected from 178 breast cancer patients who underwent ALND in Nagasaki University Hospital, Japan, between 2005 and 2017. Lymphedema was defined as symptomatic arm swelling with &gt;2 cm difference in circumference of the arm compared with that of the contralateral arm. We classified the patients with and without lymphedema, and compared them regarding surgical and pathological findings. Univariate and multivariate analyses were performed to evaluate the risk factors, using the χ2 test, Student's t-test and Cox logistic regression analysis.

Results: Prevalence of lymphedema was 16% (28/178 patients) and mean time interval from surgery to development of lymphedema was 463 days. In univariate analysis, there was a significant difference in postmastectomy radiation therapy (PMRT) (p = 0.02) and the number of patients with &gt;18 dissected ALNs (p = 0.02). Body mass index (p = 0.6), administration of docetaxel (p = 0.2), and smoking (p = 0.07) did not significantly increase lymphedema. In multivariate analysis, PMRT (p = 0.01) and dissection of &gt;18 ALNs (p = 0.001) significantly increased the risk of lymphedema, whereas smoking did not (p = 0.4).

Conclusion: Our study suggested that PMRT and number of dissected ALNs were risk factors for lymphedema. Aggressive and empiric ALND might be associated with axillary lymph duct damage. Therefore, we plan to introduce axillary reverse mapping using indocyanine green to reduce the risk of lymphedema in breast cancer patients who undergo ALND.

Citation Format: Hara Y, Otsubo R, Inamasu E, Matsumoto M, Yano H, Sakimura C, Kuba S, Yamanouchi K, Eguchi S, Nagayasu T. Prevalence and risk factors associated with development of lymphedema after axillary lymph node dissection among breast cancer patients: Single center retrospective study [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-35.

Extraction Mechanism of Ferric and Manganese Ions with Aqueous Two-phase System Formed by Ionic Liquid and Polyethylene Glycol

In this work, we employed an aqueous two-phase system formed by an ionic liquid and polyethylene glycol for the separation of Fe(III), which is the most commonly used metal in the world, and Mn(II), which is currently used in many industries. We found that the extraction mechanisms of Fe(III) and Mn(II) were strongly influenced by the concentration of the hydrochloric acid that dissolved the metal salt. The ion pair reaction was the predominant mechanism that generated the Fe(III) and Mn(II) extractions. At a lower concentration of hydrochloric acid, metal ions were extracted because of the reaction between a metal cation and a dodecylsulfonate anion. At a higher concentration of hydrochloric acid, the reaction between a metal chlorocomplex anion and a hexylmethylimidazolium cation also proceeded. The aqueous two-phase system, composed of ionic liquid and polyethylene glycol, is promising for metal separation based on the difference in the affinity of metal with alkyl-sulfonate in a low HCl concentration and in the stability constant of metal chlorocomplex in a high HCl concentration. The maximum extractability of Fe(III) and Mn(III) was 57.8 and 75.3 %, respectively, with 0.3 mol dm–3 hydrochloric acid concentration.

Thermoelectric properties of dispersant-free semiconducting single-walled carbon nanotubes sorted by a flavin extraction method

Flavin extraction method realized an improved power factor by easy removal of the dispersant from semiconducting SWNT sheet.

Clinical Utility of Intraoperative Motor-Evoked Potential Monitoring to Prevent Postoperative Spinal Cord Injury in Thoracic and Thoracoabdominal Aneurysm Repair: An Audit of the Japanese Association of Spinal Cord Protection in Aortic Surgery Database

BACKGROUND

Spinal cord ischemic injury is the most devastating sequela of descending and thoracoabdominal aortic surgery. Motor-evoked potentials (MEPs) have been used to intraoperatively assess motor tract function, but it remains unclear whether MEP monitoring can decrease the incidence of postoperative motor deficits. Therefore, we reviewed multicenter medical records of patients who had undergone descending and thoracoabdominal aortic repair (both open surgery and endovascular repair) to assess the association of MEP monitoring with postoperative motor deficits.

METHODS

Patients included in the study underwent descending or thoracoabdominal aortic repair at 12 hospitals belonging to the Japanese Association of Spinal Cord Protection in Aortic Surgery between 2000 and 2013. Using multivariable mixed-effects logistic regression analysis, we investigated whether intraoperative MEP monitoring was associated with postoperative motor deficits at discharge after open and endovascular aortic repair.

RESULTS

We reviewed data from 1214 patients (open surgery, 601 [49.5%]; endovascular repair, 613 [50.5%]). MEP monitoring was performed in 631 patients and not performed in the remaining 583 patients. Postoperative motor deficits were observed in 75 (6.2%) patients at discharge. Multivariable logistic regression analysis revealed that postoperative motor deficits at discharge did not have a significant association with MEP monitoring (adjusted odds ratio [OR], 1.13; 95% confidence interval [CI], 0.69-1.88; P = .624), but with other factors: history of neural deficits (adjusted OR, 6.08; 95% CI, 3.10-11.91; P < .001), spinal drainage (adjusted OR, 2.14; 95% CI, 1.32-3.47; P = .002), and endovascular procedure (adjusted OR, 0.45; 95% CI, 0.27-0.76; P = .003). The sensitivity and specificity of MEP <25% of control value for motor deficits at discharge were 37.8% (95% CI, 26.5%-49.5%) and 95.5% (95% CI, 94.7%-96.4%), respectively.

CONCLUSIONS

MEP monitoring was not significantly associated with motor deficits at discharge.

Thromboxane Generation in Patients with Essential Hypertension or Cerebrovascular Disease and Effect of Oral Aspirin

The ability of platelets to synthesize thromboxane B2 (TxB2) from arachidonic acid (AA) or prostaglandin H2 (PGH2) was studied in 26 control subjects, 40 patients with essential hypertension, 20 patients with cerebrovascular disease (CVD) not taking aspirin and 11 patients with CVD taking aspirin. The activity of platelets to form TxB2 from AA or PGH2 was measured using 1 — 14C arachidonic acid or 1—14C PGH2 as a substrate. There was no significant difference in TxB2 generation from AA or PGH2 among the platelets collected from the control subjects, hypertensive patients and CVD patients not taking aspirin.

In CVD patients taking aspirin, marked suppression was observed in TxB2 synthesis from AA, but no suppression in TxB2 synthesis from PGH2. At least 750 mg aspirin per day were required for nearly complete suppression of TxB2 generation from AA.

Prognostic value of sequencing-based minimal residual disease detection in patients with multiple myeloma who underwent autologous stem-cell transplantation

Background

Most patients with multiple myeloma (MM) are considered to be incurable, and relapse owing to minimal residual disease (MRD) is the main cause of death among these patients. Therefore, new technologies to assess deeper response are required.

Patients and methods

We retrospectively analyzed 125 patients with MM who underwent high-dose melphalan plus autologous stem-cell transplantation (ASCT) to detect MRD in autograft/bone marrow (BM) cells using a next-generation sequencing (NGS)-based method and allele-specific oligonucleotide-polymerase chain reaction (ASO-PCR).

Results

NGS-based method was applicable to 90% and this method had at least one to two logs greater sensitivity compared to ASO-PCR. MRD negative by NGS [MRD^NGS(−)] (defined as <10⁻⁶) in post-ASCT BM cases (n = 26) showed a significantly better progression-free survival (PFS) (96% at 4 years, P < 0.001) and overall survival (OS) (100% at 4 years, P =0.04) than MRD^NGS(+) in post-ASCT BM cases (n = 25). When restricting the analysis to the 39 complete response cases, patients who were MRD^NGS(−) (n = 24) showed a significantly better PFS than those that were MRD^NGS(+) (n = 15) (P =0.02). Moreover, MRD^NGS(−) in post-ASCT BM cases (n = 12) showed significantly a better PFS than MRD^NGS(+) cases (n = 7) where MRD was not detected by ASO-PCR (P = 0.001). Patients whose autografts were negative by NGS-based MRD assessment (<10⁻⁷) (n = 19) had 92% PFS and 100% OS at 4 years post-ASCT. Conversely, the NGS-based MRD positive patients who received post-ASCT treatment using novel agents (n = 49) had a significantly better PFS (P = 0.001) and tended to have a better OS (P= 0.214) than those that were untreated (n = 33).

Conclusions

Low level MRD detected by NGS-based platform but not ASO-PCR has significant prognostic value when assessing either the autograft product or BM cells post-ASCT.

Does Shortened Application Time Affect Long-Term Bond Strength of Universal Adhesives to Dentin?

OBJECTIVE

This study evaluated the effect of shortened application time on long-term bond strength with universal adhesives.

METHODS AND MATERIALS

Three universal adhesives were used: Clearfil Universal Bond (CU, Kuraray Noritake Dental Inc, Tokyo, Japan), Scotchbond Universal Adhesive (SB, 3M ESPE, St Paul, MN, USA) or G-Premio Bond (GP, GC Corp, Tokyo, Japan). Sixty molars were cut to expose midcoronal dentin and prepared with a regular diamond bur. Each adhesive was applied either according to the manufacturer's instruction or with shortened time. Specimens were stored in distilled water at 37°C for 24 hours and then cut into resin-dentin sticks. Microtensile bond strength (μTBS) was tested after either 24 hours or 1 year of water storage. Data were analyzed by the three-way ANOVA and Duncan tests ( α=0.05). Fracture modes were analyzed under a scanning electron microscope (SEM). One dentin stick per group was selected after fracture mode analysis and further observed using transmission electron microscopy (TEM). Six additional dentin discs were prepared and conditioned with each adhesive under the different application time to observe the adhesive-smear layer interaction by SEM.

RESULTS

Shortened application time affected the μTBS ( p<0.001) while storage time did not affect bond strength ( p=0.187). A significant effect of shortened application time on μTBS was observed in the CU at 1 year and in the GP at both storage times.

CONCLUSIONS

One-year storage time had no effect on the μTBS of universal adhesives to bur-cut dentin. The performance of universal adhesives can be compromised when applied using a shortened application time.

ADAMTS13 activity and genetic mutations in Japan

Thrombotic thrombocytopenic purpura (TTP), a life threatening disease, can be induced by congenital or acquired deficiency of plasma metalloprotease ADAMTS13. Since the publication of the first genetic analysis in patients with congenital ADAMTS13 deficiency in 2001, more than 100 genetic defects in the ADAMTS13 gene have been reported worldwide. Genetic analysis in patients with ADAMTS13 deficiency has greatly contributed to the understanding of the etiology of TTP. A rapid and quantitative assay method for the plasma ADAMTS13 activity was developed recently in 2005 and opened a new area of TTP research – namely genetic research using a general population to evaluate age and gender differences of ADAMTS13 activity as well as phenotype – genotype correlations of genetic polymorphisms and estimation of a homozygote or a compound heterozygote ADAMTS13 deficiencies. The Japanese general population study included 3616 individuals with an age between 30 – 80 years confirming other studies that while ADAMTS13 activity decreased with age, VWF antigen increased and VWF antigen levels are lowest in blood group O indviduals, whereas ADAMTS13 activity levels were not associated with the AB0 blood group. 25 polymorphisms with a minor allele frequency of more than 0.01 were found, among them 6 missense mutations and 19 synonymous mutations, except P475S missense polymorphisms that was only idenitified in an East Asian population, characterized by reduced ADAMTS13 activity. Prevalence of congenital ADAMTS13 deficiency in the Japanese population was estimated about one individual in 1.1 × 106 to be homozygote or compound heterozygote for ADAMTS13 deficiency. So far more than 40 mutations in Japanese congenital TTP patients were found, but R193W, Q449*, C754Afs*24 (c.2259delA) and C908Y were identified in more than four patients suggesting the precipitaion of these mutations in the Japanese population.

Changes in dermal structure and skin oxidative stress in overweight and obese Japanese males after weight loss: a longitudinal observation study

BACKGROUND/PURPOSE

Previous studies have reported decreased dermal echogenicity and increased skin oxidative stress in overweight males. However, it is unknown whether these skin parameters of overweight and obese people are similar to those of individuals exhibiting a normal body weight following weight loss. The purpose of this study was to (1) compare the changes in the dermal structure parameters and levels of skin oxidative stress before and after weight loss in overweight and obese people in Japan and (2) to clarify how these aspects changed when body weight would be reduced to normal body weight.

METHODS

Male volunteers with a body mass index of ≥25 kg/m² were recruited. The dermal structure was visualized and dermal echogenicity and thickness were measured using ultrasound scanners. The mRNA expression level of heme oxygenase-1 in the hair follicles was quantitatively analyzed as a marker of skin oxidative stress.

RESULTS

When overweight individuals in their 20s to 30s reduced their weight to normal, decreased dermal thickness in the abdominal region was observed in 50% of the subjects; however, no increase in dermal echogenicity was observed. A decrease in dermal thickness and an increase in dermal echogenicity in the thighs was observed in 83.3% of the subjects. No decrease in the level of dermal oxidative stress was observed.

CONCLUSION

The dermal structure in the thighs of overweight young individuals can be improved to the level of the structure in those of normal body weight individuals following weight loss.

Correction to: Cerebrovascular CO2 reactivity during isoflurane-nitrous oxide anesthesia in patients with chronic renal failure

In the original publication of the article, the first sentence was published incorrectly under the section "Patients and preoperative assessment". The correct sentence should read as, "The Yamaguchi University Graduate School of Medicine Ethics Committee for Human Study approved the study protocol (18th August 2004: H16-71)".

Cerebrovascular CO2 reactivity during isoflurane-nitrous oxide anesthesia in patients with chronic renal failure

PURPOSE

We assessed the cerebrovascular CO₂ reactivity (CO₂R) in chronic renal failure (CRF) patients without diabetes mellitus (DM), uncontrolled hypertension, peripheral vascular disease, or neurological disease under isoflurane-nitrous oxide anesthesia.

METHODS

Forty-nine patients undergoing surgery, including 36 CRF patients (30 receiving dialysis and six pre-dialysis patients) and 13 patients without CRF (controls). Middle cerebral artery flow velocity (VMCA) was measured by transcranial Doppler ultrasonography at an end-tidal CO₂ of 35 to 45 mmHg. CO₂R was calculated as an absolute value (change in VMCA per mmHg PaCO₂) and a relative value (absolute CO₂R/baseline VMCA × 100). Factors associated with CO₂R were evaluated simultaneously.

RESULTS

Despite no significant differences in the absolute and relative values of CO₂R between the CRF (mean 2.5 cm/s/mmHg; median 5.0%/mmHg) and control (2.4 cm/s/mmHg; 5.0%/mmHg) groups, blood urea nitrogen (BUN) concentrations in the CRF group correlated inversely with both absolute and relative CO₂R. BUN concentration was higher (mean 72 versus 53 mg/dl, p = 0.006) and relative CO₂R was lower (mean 2.6 versus 5.7%/mmHg, p = 0.011) in patients with pre-dialysis CRF (n = 6) versus CRF patients receiving dialysis (n = 30).

CONCLUSIONS

CO₂R in CRF patients was not significantly different from that in controls. However, in CRF patients with high BUN concentrations, CO₂R might be impaired, leading to reduced cerebrovascular reserve capacity. Because DM is a major cause of CRF and we excluded DM patients, our results might not be applicable to patients with DM-induced CRF.