Ketamine as an Alternative Anesthetic for Augmenting Seizure Durations During Electroconvulsive Therapy: A Retrospective Observational Study

OBJECTIVE

Electroconvulsive therapy (ECT) is highly effective for severe psychiatric disorders; however, short seizure durations may lead to ineffective therapy. This retrospective study aimed to examine the risks and benefits of switching to ketamine anesthesia to augment seizure durations during an acute course of ECT.

METHODS

We included 33 patients who underwent ketamine anesthesia due to suboptimal seizures during an acute course of ECT. We assessed seizure duration, stimulus dose, hemodynamic variability, and postseizure complications before and after switching to ketamine.

RESULTS

Age was significantly associated with suboptimal seizures during ECT (P = 0.040). After switching to ketamine, 32 patients (97%) experienced prolonged seizure duration. Ketamine significantly prolonged both electroencephalogram and motor seizure durations with a mean difference of 34.6 seconds (95% confidence interval [CI], 26.4-42.7 seconds; P < 0.001) and 26.6 seconds (95% CI, 19.6-33.6 seconds; P < 0.001), respectively. It also significantly reduced stimulus dose (mean difference, -209.5 mC [95% CI, -244.9 to -174.1 mC]; P < 0.001). In addition, maximum changes in systolic blood pressure and heart rate during ECT sessions significantly increased with ketamine (mean difference, 27.2 mm Hg [95% CI, 12.0-42.4 mm Hg; P = 0.001]; 25.7 beats per minute [95% CI, 14.5-36.8 beats per minute; P < 0.001], respectively). Patients reported more headaches with ketamine (P = 0.041).

CONCLUSIONS

Our results provide evidence that ketamine as an alternative anesthetic can augment seizure durations in specific patients experiencing suboptimal seizures during an acute course of ECT. However, its use requires greater attention to circulatory management and postseizure complications.

Predicting the Outcome of the Buckwheat Oral Challenge Test: A First Evaluation Assuming a Single Serving of Boiled Buckwheat Noodles

Summary

Background. Global increase in buckwheat consumption has led to a surge in buckwheat allergy reports. However, studies scrutinizing the predictive accuracy of buckwheat-specific immunoglobulin E (IgE) antibody levels in correlation with symptom manifestation remain limited. A critical concern is the discrepancy between the total buckwheat amount featured in prior studies and the quantity consumed per occasion. We aimed to determine open Oral Food Challenge (OFC) positivity rates with buckwheat, using a single serving of boiled buckwheat noodles, and assess the predictability of positive responses using buckwheat-specific IgE levels. Methods. Patients aged 20 years or younger, suspected of buckwheat allergy, were subjected to an OFC involving consumption of 100 g (4800 mg of protein) of boiled buckwheat noodles for those under six years, and 200 g (9600 mg of protein) for those six years or older. The predictive accuracy of the OFC, corresponding with buckwheat-specific IgE antibody levels, was evaluated using Receiver Operating Characteristic (ROC) analysis. Results. Our study involved 80 patients who undertook a buckwheat OFC. Among these, 14 (17.5%) tested positive for a buckwheat allergy, with 3 (3.8%) developing anaphylaxis. The comparative analysis of buckwheat-specific IgE antibody levels did not offer a reliable predictive measure for OFC outcomes. However, a past history of symptom manifestation following buckwheat consumption was significantly correlated with a positive OFC. Conclusions. Forecasting OFC outcomes based on buckwheat-specific IgE antibody levels poses a challenge, even when taking into account the total quantity of buckwheat that can be consumed in a single occasion.

The Safety and Strategies for Reinitiating Electroconvulsive Therapy After ECT-Induced Takotsubo Cardiomyopathy: A Case Report and Systematic Review

OBJECTIVES

Takotsubo cardiomyopathy (TCM) is a life-threatening complication of electroconvulsive therapy (ECT). We report the case of a 66-year-old woman who was rechallenged with ECT after ECT-induced TCM. Moreover, we have made a systematic review to assess the safety of and strategies for reinitiating ECT after TCM.

METHODS

We searched for published reports on ECT-induced TCM since 1990 in MEDLINE (PubMed), Scopus, Cochrane Library, ICHUSHI, and CiNii Research.

RESULTS

A total of 24 ECT-induced TCM cases were identified. Patients who developed ECT-induced TCM were predominantly middle-aged and older women. There was no specific trend in anesthetic agents used. Seventeen (70.8%) cases developed TCM by the third session in the acute ECT course. Eight (33.3%) cases developed ECT-induced TCM despite the use of β-blockers. Ten (41.7%) cases developed cardiogenic shock or abnormal vital signs related to cardiogenic shock. All cases recovered from TCM. Eight (33.3%) cases tried to receive ECT retrial. The duration until ECT retrial was between 3 weeks and 9 months. The most common preventive measures during ECT retrial were related to β-blockers; however, the type, dose, and route of administration of β-blockers varied. In all cases, ECT could be reperformed without TCM recurrence.

CONCLUSIONS

Electroconvulsive therapy-induced TCM is more likely to cause cardiogenic shock than nonperioperative cases; nevertheless, it has good prognosis. Cautious reinitiation of ECT after TCM recovery is possible. Further studies are required to determine preventive measures for ECT-induced TCM.

Hemodynamic impact of ephedrine on hypotension during general anesthesia: a prospective cohort study on middle-aged and older patients

BACKGROUND

Ephedrine is a mixed α- and β-agonist vasopressor that is frequently used for the correction of hypotension during general anesthesia. β-responsiveness has been shown to decrease with age; therefore, this study aimed to determine whether aging would reduce the pressor effect of ephedrine on hypotension during general anesthesia.

METHODS

Seventy-five patients aged ≥ 45 years were included in this study, with 25 patients allocated to each of the three age groups: 45-64 years, 65-74 years, and ≥ 75 years. All patients received propofol, remifentanil, and rocuronium for the induction of general anesthesia, followed by desflurane and remifentanil. Cardiac output (CO) was estimated using esCCO technology. Ephedrine (0.1 mg/kg) was administered for the correction of hypotension. The primary and secondary outcome measures were changes in the mean arterial pressure (MAP) and CO, respectively, at 5 min after the administration of ephedrine.  RESULTS: The administration of ephedrine significantly increased MAP (p < 0.001, mean difference: 8.34 [95% confidence interval (CI), 5.95-10.75] mmHg) and CO (p < 0.001, mean difference: 7.43 [95% CI, 5.20-9.65] %) across all groups. However, analysis of variance revealed that the degree of elevation of MAP (F [2, 72] = 0.546, p = 0.581, η2 = 0.015 [95% CI, 0.000-0.089]) and CO (F [2, 72] = 2.023, p = 0.140, η2 = 0.053 [95% CI, 0.000-0.162]) did not differ significantly among the groups. Similarly, Spearman's rank correlation and multiple regression analysis revealed no significant relation between age and the changes in MAP or CO after the administration of ephedrine.

CONCLUSION

The administration of ephedrine significantly increased MAP and CO; however, no significant correlation with age was observed in patients aged > 45 years. These findings suggest that ephedrine is effective for the correction of hypotension during general anesthesia, even in elderly patients.

TRIAL REGISTRATION

UMIN-CTR (UMIN000045038; 02/08/2021).

Comparison of hemodynamics during induction of general anesthesia with remimazolam and target-controlled propofol in middle-aged and elderly patients: a single-center, randomized, controlled trial

BACKGROUND

Remimazolam confers a lower risk of hypotension than propofol. However, no studies have compared the efficacy of remimazolam and propofol administered using target-controlled infusion (TCI). This study aimed to investigate hemodynamic effects of remimazolam and target-controlled propofol in middle-aged and elderly patients during the induction of anesthesia.

METHODS

Forty adults aged 45-80 years with the American Society of Anesthesiologists Physical Status 1-2 were randomly assigned to remimazolam or propofol group (n = 20 each). Patients received either remimazolam (12 mg/kg/h) or propofol (3 μg/mL, TCI), along with remifentanil for inducing anesthesia. We recorded the blood pressure, heart rate (HR), and estimated continuous cardiac output (esCCO) using the pulse wave transit time. The primary outcome was the maximum change in mean arterial pressure (MAP) after induction. Secondary outcomes included changes in HR, cardiac output (CO), and stroke volume (SV).

RESULTS

MAP decreased after induction of anesthesia in both groups, without significant differences between the groups (- 41.1 [16.4] mmHg and - 42.8 [10.8] mmHg in remimazolam and propofol groups, respectively; mean difference: 1.7 [95% confidence interval: - 8.2 to 4.9]; p = 0.613). Furthermore, HR, CO, and SV decreased after induction in both groups, without significant differences between the groups. Remimazolam group had significantly shorter time until loss of consciousness than propofol group (1.7 [0.7] min and 3.5 [1.7] min, respectively; p < 0.001). However, MAP, HR, CO, and SV were not significantly different between the groups despite adjusting time until loss of consciousness as a covariate. Seven (35%) and 11 (55%) patients in the remimazolam and propofol groups, respectively, experienced hypotension (MAP < 65 mmHg over 2.5 min), without significant differences between the groups (p = 0.341).

CONCLUSIONS

Hemodynamics were not significantly different between remimazolam and target-controlled propofol groups during induction of anesthesia. Thus, not only the choice but also the dose and usage of anesthetics are important for hemodynamic stability while inducing anesthesia. Clinicians should monitor hypotension while inducing anesthesia with remimazolam as well as propofol.

TRIAL REGISTRATION

UMIN-CTR (UMIN000045612).

Transition in eye gaze as a predictor of emergence from general anesthesia in children and adults: a prospective observational study

BACKGROUND

It is useful to monitor eye movements during general anesthesia, but few studies have examined neurological finding of the eyes during emergence from general anesthesia maintained with short-acting opioids and volatile anesthetics.

METHODS

Thirty children aged 1-6 years and 30 adults aged 20-79 years were enrolled. Patients received general anesthesia maintained with sevoflurane and remifentanil. The timing of three physical-behavioral responses-eye-gaze transition (the cycle from conjugate to disconjugate and back to conjugate), resumption of somatic movement (limbs or body), and resumption of respiration-were recorded until spontaneous awakening. The primary outcome measure was the timing of the physical-behavioral responses. Secondary outcome measures were the incidence of eye-gaze transition, and the bispectral index, concentration of end-tidal sevoflurane, and heart rate at the timing of eye-gaze transition.

RESULTS

Eye-gaze transition was evident in 29 children (96.7%; 95% confidence interval, 82.8-99.9). After the end of surgery, eye-gaze transition was observed significantly earlier than resumption of somatic movement or respiration (472 [standard deviation 219] s, 723 [235] s, and 754 [232] s, respectively; p < 0.001). In adults, 3 cases (10%; 95% CI, 0.2-26.5) showed eye-gaze transition during emergence from anesthesia. The incidence of eye-gaze transition was significantly lower in adults than in children (p < 0.001).

CONCLUSION

In children, eye-gaze transition was observed significantly earlier than other physical-behavioral responses during emergence from general anesthesia and seemed to reflect emergence from anesthesia. In contrast, observation of eye gaze was not a useful indicator of emergence from anesthesia in adults.

Prediction of clinical outcomes in patients with coronavirus disease 2019 using high-sensitive troponin I and N-terminal pro-B-type natriuretic peptide

Background

Several comorbidities, including cardiovascular diseases or myocardial injury, are reported to be associated with poor prognosis in patients with Coronavirus disease 2019 (COVID-19). However, detailed prognostic analysis of myocardial injury by various biomarkers in COVID-19 patients is limited.

Purpose

This study aims to explore the prognostic values of high-sensitive Troponin I (hsTnI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) for COVID-19 patients using Japanese real-world data.

Methods

The COVID-MI study is a retrospective cohort study that enrolls consecutive laboratory-confirmed COVID-19 patients admitted to the hospital from July 2020 to September 2021. We collected clinical data, including cardiac biomarker values, by chart review. If the prespecified biomarkers in concern were not available, we measured them using the institutional serum blood bank, which enrolled patients prospectively from July 2020. Patients with available biomarkers were analyzed according to the values of hsTnI or NT-proBNP, using the clinically relevant thresholds (hsTnI: 5 ng/L and 99th percentile of the upper reference limit [99%ile URL], and NT-proBNP: 125 pg/mL and 900 pg/mL). The primary outcome measure was all-cause death. Secondary outcome measures included acute respiratory distress syndrome, myocardial infarction, myocarditis/pericarditis, venous thromboembolism, cerebral infarction, and bleeding events.

Results

We enrolled 917 patients with COVID-19 confirmed by viral nucleic acid amplification test. The mean age was 61 years, and 591 patients (64%) were men. On admission, the number of patients classified as severe or critical COVID-19 was 515 (56%) and 85 (8.7%), respectively. Among the 544 patients with hsTnI values, 365 (67%) patients had elevated hsTnI of ≥5 ng/L, and 134 patients (25%) had TnI of ≥99%ile URL. Besides, among 546 patients with NT-proBNP values, 295 patients (54%) had elevated NT-pro-BNP of ≥125 pg/mL, and 93 patients (17%) had NT-proBNP of ≥900 pg/mL. The median follow-up period was 31 days (interquartile range: 11–90 days). In cumulative incidence analysis, higher levels of hsTnI and NT-proBNP were associated with significantly higher mortality (hsTnI: &lt;5 ng/L group; 8.8%, 5 ng/L to 99%ile URL group; 19%, and ≥99%ile URL group; 37%, P&lt;0.001, and NT-proBNP: &lt;125 pg/mL group; 7.8%, 125 to 900 pg/mL group; 21%, and ≥900 pg/mL group; 45%, P&lt;0.001). The adjusted risk for all-cause death remained significant for each threshold of cardiac biomarkers (hsTnI ≥99%ile URL: hazard ratio [HR] 1.98, 95% confidence interval [CI] 1.11–3.54, P=0.02, and NT-proBNP ≥900 pg/mL: HR 3.60, 95% CI 1.86–6.98, P&lt;0.001).

Conclusion

Elevation of hsTnI or NT-proBNP was associated with poor prognosis in the current relatively severely ill COVID-19 patients. Measuring hsTnI or NT-proBNP can be an attractive option for risk stratification and deciding appropriate management in patients with COVID-19.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): Institutional Research Fund at Kobe City Medical Center General Hospital

General Anesthesia in a Patient With Neuronal Intranuclear Inclusion Disease: A Case Report

Neuronal intranuclear inclusion disease (NIID) is a progressive neurodegenerative disease with diverse clinical manifestations, including dementia and muscle weakness. We summarize anesthetic considerations in reporting general anesthesia for a 58-year-old man with bladder dysfunction and cerebellar ataxia who was diagnosed with NIID. The patient developed postinduction hypotension relevant to autonomic neuropathy. The potential risks, such as prolonged reaction to neuromuscular blocking agent, postoperative delirium, and worsening of NIID-related symptoms, were also considered. The responsiveness to anesthetics may vary widely from case t case. As the number of NIID cases increases, a better understanding of NIID is needed.

Estimation of possible candidates for ivabradine in rural Japan and investigation of their clinical characteristics

Background

In Japan, ivabradine is indicated in patients with heart failure (HF) with sinus rhythm and a resting heart rate (HR) ≥75/min under standard treatment. Particularly, it is effective for HF with reduced left ventricular ejection fraction (LVEF). However, elderly people have a higher incidence of atrial fibrillation than young people, and their sinus node function is further deteriorated, resulting in a lower intrinsic HR. In addition, Japan is an ultra-aging society, especially in the countryside; therefore, the target patients for ivabradine may be limited in these regions.

Purpose

We sought to estimate the possible candidates for ivabradine and investigate their clinical characteristics in our hospital located in rural Japan.

Method and results

We retrospectively studied 14733 consecutive patients who were suspected heart disease who underwent echocardiography between January 2006 and October 2018 in Kitaishikai Hospital located in Ozu city (Proportion of the population aged ≥65 years: 34%, in 2015) and did not take ivabradine treatment. Of these, 187 patients with hemodynamically stable condition whose E/A ratio was measured and met the criteria of LVEF &lt;40% and HR ≥75 /min were confirmed. Of these, 153 patients reached HR &lt;75 /min with additional intensive medication within one year after the index echocardiography (Controlled group; mean HR: 82 to 62/min). The remaining 34 patients with uncontrolled HR (Uncontrolled group; mean HR: 84 to 82/min) were considered possible candidates for ivabradine (34/14733: 0.23%, 2.6 patients per year; median age, 74 years; male, 56%; median LVEF, 32%; ischemic cardiomyopathy, 53%). In the comparison of clinical and echocardiographic parameters in these two groups, Uncontrolled group had a significantly smaller left ventricular diastolic volume index (71 [59–85] vs 82 [66–109] /ml/m2, p=0.02), left ventricular systolic volume index (50 [39–59] vs 59 [42–80] / ml/m2, p=0.04), stroke volume index (22 [18–26] vs 26 [20–32] /ml/m2, p=0.02), left atrial volume index (47 [40–64] vs 59 [45–71] /ml/m2, p=0.02), and more hemodialysis (12 vs 3%, p=0.04) than Controlled group. However, the discrimination ability of these parameters for identifying Uncontrolled group was modest (Figure).

Conclusion

In rural Japan, possible candidates for ivabradine may be rare, so daily attention should be paid. Patients with reduced ejection fraction, small left ventricle, and hemodialysis may be the possible targets for this therapy.

Funding Acknowledgement

Type of funding sources: None.

Left ventricular longitudinal shortening at cardiac base as a determinant of left atrial reservoir function in cardiac amyloidosis

Objective

To investigate a mechanistic determinant of left atrial (LA) reservoir function in patients presenting left ventricular (LV) hypertrophy, and clarify diagnostic and prognostic values of LA reservoir strain in patients with cardiac amyloidosis (CA).

Methods

Three-hundred sixty patients (median age: 68 years, male gender: 65%) with left ventricular hypertrophy (LVH) assessed by echocardiography were retrospectively included. The LVH etiologies were diagnosed by any of biopsy, cardiac magnetic resonance imaging or 99mTc-PYP scintigraphy. LV segmental longitudinal strain was estimated from apical three views, and LA reservoir strain was measured from an apical 4-chamber view.

Results

The LVH etiologies were confirmed with CA in 81 patients, hypertensive heart disease in 87 patients, hypertrophic cardiomyopathy in 143 patients, and miscellaneous disorders in 49 patients. The median (25th, 75th percentile) value of LV ejection fraction was 59% (48–67). LV basal longitudinal strain and LA reservoir strain were significantly reduced in patients with CA compared with those with other etiologies; LV basal strain: 5.4% (3.9–8.7) vs. 11.9% (9.3–14.6), LA reservoir strain: 9.2% (6.3–12.3) vs. 17.5% (11.3–24.1), p&lt;0.01 respectively. LV basal strain was significantly correlated with LA reservoir strain in patients with CA (r=0.57, p&lt;0.01) and in those with other etiologies (r=0.45, p&lt;0.01). The area under the receiver-operating characteristic curves of LA reservoir strain and E/e' (0.78 and 0.74) to identify CA etiology were significantly larger than that of LA volume index (0.62) (p&lt;0.01). During the follow-up period (median 2.9 years), 53 patients experienced heart failure hospitalization. The Cox regression model including age, gender, LV ejection fraction, E/e' and LA reservoir strain showed that male gender (hazard ratio: 0.46, p=0.03), E/e' (hazard ratio: 1.04, p&lt;0.01) and LA reservoir strain (hazard ratio: 0.94, p&lt;0.01) independently predicted heart failure hospitalization.

Conclusions

The decrease of LV longitudinal shortening at cardiac base could worsen LA reservoir function especially in patients with CA. LA reservoir strain might be an alternative measure to identify CA etiology and have a predictive value of heart failure hospitalization in patients with LV hypertrophy.

Funding Acknowledgement

Type of funding sources: None.

Extent of absent end-diastolic flow in umbilical artery and outcome of pregnancy

OBJECTIVE

To investigate if the extent of absent end-diastolic flow (AEDF) on umbilical artery (UA) Doppler velocimetry predicts pregnancy outcome.

METHODS

This was a retrospective observational study based on data from 25 000 Doppler examinations of UA flow performed between 1998 and 2017 at the Blood Flow Laboratory, Level III Perinatal Center, Lund, Sweden. All pregnancies with AEDF in the UA were identified, and the duration of AEDF as a proportion of the total duration of the cardiac cycle (T_a /T_tot ratio) was measured in digital images of the Doppler spectrum recorded at the last examination showing AEDF before delivery. Clinical data on pregnancies and neonatal outcomes were extracted from the regional perinatal database and the hospital patient records. The predictive performance of the T_a /T_tot ratio for intrauterine death and any (intrauterine or postnatal) death was assessed.

RESULTS

A total of 170 fetuses (122 (72%) singletons and 48 (28%) twins) were included in the study. Median gestational age at birth was 189.5 days (range, 163-279 days) (i.e. 27 + 0 weeks (range, 23 + 2 to 39 + 6 weeks)), birth weight was 650 g (range, 320-3326 g) and deviation from expected birth weight (standard deviation score) was -2.975 (range, -6.38 to 0.69). There were 15 (9%) intrauterine and 26 (15%) postnatal deaths. The principal outcome variables and their relationship with Doppler velocimetry results did not differ significantly between singletons and twins, giving a rationale for using the T_a /T_tot ratio in the total study group. Mean T_a /T_tot ratio was 0.42 ± 0.08 and 0.34 ± 0.08 in stillborn and liveborn fetuses, respectively (P = 0.002). For fetuses examined before 30 weeks' gestation, a T_a /T_tot ratio cut-off of 0.30 predicted intrauterine death with 92% sensitivity and a negative predictive value (NPV) of 98% (area under receiver-operating-characteristics curve (AUC), 0.74) and predicted any death with 83% sensitivity and a NPV of 85% (AUC, 0.66).

CONCLUSIONS

In fetuses with AEDF in the UA, duration of absent flow for at least 30% of the total cardiac cycle length might predict the risk of fetal demise, even when assessed before 30 weeks' gestation. This finding is particularly relevant to growth-restricted fetuses. After evaluation in further studies, the extent of AEDF might facilitate obstetric decision-making in very preterm growth-restricted fetuses. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

A comparison of thyroidal protection by iodine and perchlorate against radioiodine exposure in Caucasians and Japanese

Radioactive iodine released in nuclear accidents may accumulate in the thyroid and by irradiation enhances the risk of cancer. Radioiodine uptake into the gland can be inhibited by large doses of stable iodine or perchlorate. Nutritional iodine daily intake may impact thyroid physiology, so that radiological doses absorbed by the thyroid as well as thyroid blocking efficacy may differ in Japanese with a very rich iodine diet compared to Caucasians. Based on established biokinetic-dosimetric models for the thyroid, we derived the parameters for Caucasians and Japanese to quantitatively compare the effects of radioiodine exposure and the protective efficacy of thyroid blocking by stable iodine at the officially recommended dosages (100 mg in Germany, 76 mg in Japan) or perchlorate. The maximum transport capacity for iodine uptake into the thyroid is lower in Japanese compared to Caucasians. For the same radioiodine exposure pattern, the radiological equivalent thyroid dose is substantially lower in Japanese in the absence of thyroid blocking treatments. In the case of acute radioiodine exposure, stable iodine is less potent in Japanese (ED50 = 41.6 mg) than in Caucasians (ED50 = 2.7 mg) and confers less thyroid protection at the recommended dosages because of a delayed responsiveness to iodine saturation of the gland (Wolff-Chaikoff effect). Perchlorate (ED50 = 10 mg in Caucasians) at a dose of 1000 mg has roughly the same thyroid blocking effect as 100 mg iodine in Caucasians, whereas it confers a much better protection than 76 mg iodine in Japanese. For prolonged exposures, a single dose of iodine offer substantially lower protection than after acute radioiodine exposure in both groups. Repetitive daily iodine administrations improve efficacy without reaching levels after acute radioiodine exposure and achieve only slightly better protection in Japanese than in Caucasians. However, in the case of continuous radioiodine exposure, daily doses of 1000 mg perchlorate achieve a high protective efficacy in Caucasians as well as Japanese (> 0.98). In Caucasians, iodine (100 mg) and perchlorate (1000 mg) at the recommended dosages seem alternatives in case of acute radioiodine exposure, whereas perchlorate has a higher protective efficacy in the case of longer lasting radioiodine exposures. In Japanese, considering protective efficacy, preference should be given to perchlorate in acute as well as prolonged radioiodine exposure scenarios.

Mice with cleavage-resistant N-cadherin exhibit synapse anomaly in the hippocampus and outperformance in spatial learning tasks

N-cadherin is a homophilic cell adhesion molecule that stabilizes excitatory synapses, by connecting pre- and post-synaptic termini. Upon NMDA receptor (NMDAR) activation by glutamate, membrane-proximal domains of N-cadherin are cleaved serially by a-disintegrin-and-metalloprotease 10 (ADAM10) and then presenilin 1(PS1, catalytic subunit of the γ-secretase complex). To assess the physiological significance of the initial N-cadherin cleavage, we engineer the mouse genome to create a knock-in allele with tandem missense mutations in the mouse N-cadherin/Cadherin-2 gene (Cdh2 R714G, I715D, or GD) that confers resistance on proteolysis by ADAM10 (GD mice). GD mice showed a better performance in the radial maze test, with significantly less revisiting errors after intervals of 30 and 300 s than WT, and a tendency for enhanced freezing in fear conditioning. Interestingly, GD mice reveal higher complexity in the tufts of thorny excrescence in the CA3 region of the hippocampus. Fine morphometry with serial section transmission electron microscopy (ssTEM) and three-dimensional (3D) reconstruction reveals significantly higher synaptic density, significantly smaller PSD area, and normal dendritic spine volume in GD mice. This knock-in mouse has provided in vivo evidence that ADAM10-mediated cleavage is a critical step in N-cadherin shedding and degradation and involved in the structure and function of glutamatergic synapses, which affect the memory function.

Impact of right ventricular contractile reserve on exercise capacity in patients with heart failure: clinical application of low-load exercise stress echocardiography

Background

The peak oxygen uptake (VO2) evaluated by the cardiopulmonary exercise test (CPX) is an established marker of exercise capacity in patients with heart failure (HF). In particular, peak VO2 &lt;14 ml/kg/min is used to be one of the criteria for heart transplantation. However, given exercise intolerance in patients with HF, it is difficult for refractory HF patients to reach sufficient exercise load. A recent report has highlighted significant impact of right ventricular (RV) function on mortality and urgent heart transplantation. Taken together, we hypothesized that the assessment of RV function was helpful to predict exercise capacity by using low-load exercise stress echocardiography (low-load ESE) in patients with HF.

Purpose

We evaluated whether RV dysfunction assessed by the low-load ESE determined a low peak VO2 &lt;14 ml/kg/min in patients with HF.

Methods

We studied 67 consecutive hospitalized patients with HF (mean age, 65 years; 75% male; mean LV ejection fraction, 36%) who underwent ESE and CPX after stabilized HF condition, and the time interval of CPX and ESE tests was within 48 hours. CPX was performed using an upright cycle ergometer by a ramp protocol, while ESE was performed using ergometer in semi-supine position and the workload was generally increased by 25 watts every 3 minutes. The low-load ESE was defined as the 25 watts exercise. The increments of RV s' velocity at tricuspid annulus and RV strain in the free wall were considered as a preservation of RV contractile reserve. Among the study population, 26 patients were performed right heart catheterization and RV dP/dt/Pmax was estimated as an invasive marker of RV contractility.

Results

The achieved intensity of exercise was 50.4±21.0 watts, and all patients completed the low-load ESE. The invasive study showed that the change of RV s' velocity during the low-load ESE significantly correlated with RV dP/dt/Pmax (r=0.706, p&lt;0.001). As shown in Figure, the non-invasive parameters of RV contractile reserve during the low-load ESE were significantly correlated with peak VO2 (RV s' velocity: r=0.787, p&lt;0.001; RV strain: r=0.244, p=0.047). ROC analysis showed that the change of RV s' velocity during the low-load ESE correctly identified patients with peak VO2 &lt;14 ml/kg/min (AUC=0.95, sensitivity 92.3%, specificity 85.2%). In terms of inter- and intra-observer variabilities, ICCs of the change of RV s' velocity were 0.86 and 0.96, and ICCs of the changes of RV strain were 0.63 and 0.70, respectively.

Conclusion

The change of RV s' velocity during the low-load ESE could determine exercise tolerance in patients with HF. The assessment of RV contractile reserve might be clinically useful to discriminate high risk HF patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

Biodegradable-polymer versus durable-polymer drug eluting stents for coronary artery disease: systematic review and a meta-analysis

Background

Biodegradable polymer drug-eluting stents (BP-DES) has been developed to overcome the potential drawbacks of the first-generation durable polymer drug-eluting stents (DP-DES). However, it is still under debate whether BP-DES is associated with superior efficacy and safety over DP-DES.

Purpose

We sought to compare the effects of BP-DES and DP-DES in patients with coronary artery disease.

Methods

We performed systematic review and a meta-analysis of randomized controlled trials comparing BP-DES and DP-DES on clinical outcomes in patients with coronary artery disease using CE-mark approved drug-eluting stents (DES) with at least 1-year follow-up. We included 32 studies involving 39,686 patients (BP-DES: 21,439 patients, and DP-DES: 18,247 patients). Primary outcome measure was target vessel failure (TVF; equivalent to the composite of cardiac death, target-vessel myocardial infarction, or ischemia-driven target vessel revascularization). We performed subgroup analysis according to the DP-DES generations (newer-generation DP-DES: 15,179patients, and first-generation DP-DES: 3,068 patients), and the effects of newer-generation DP-DES was compared with the BP-DES according to the BP-DES strut thickness (Ultra-thin strut [&lt;80μm]: 7,572 patients, Thin-strut [80–100μm]: 5,465 patients, and Thick-strut [≥80μm]: 5,876 patients).

Results

The odds for TVF was not significantly different between the BP-DES group and the DP-DES group in the entire study population (odds ratio [OR] 0.96, 95% confidence interval [CI] [0.90–1.02], P=0.20). The odds for TVF was significantly low in the BP-DES group relative to the first-generation DP-DES group, however the odds were comparable between the BP-DES group and the newer-generation DP-DES group (BP-DES versus first-generation DP-DES: OR 0.82, 95% CI [0.73–0.92], P&lt;0.001, and BP-DES versus newer-generation DP-DES: OR 1.00, 95% CI [0.93–1.08], P=0.99). We also found no significant differences between the BP-DES and newer-generation DP-DES, in all subgroups stratified by the BP-DES strut thickness (Ultra-thin strut BP-DES versus newer-generation DP-DES: OR 0.88, 95% CI [0.76–1.02], P=0.10, Thin-strut BP-DES versus newer-generation DP-DES: OR 1.01, 95% CI [0.90–1.13], P=0.89, and Thick strut BP-DES versus newer-generation DP-DES: OR 1.11, 95% CI [0.99–1.25], P=0.08).

Conclusions

In this meta-analysis of randomized controlled trials evaluating clinical outcomes, there was no significant differences between BP-DES and DP-DES. We found beneficial effects of BP-DES relative to the first-generation DP-DES, however, there was no statistical differences between BP-DES and newer-generation DP-DES, irrespective of the BP-DES strut thickness.

Pooled odds ratios for clinical outcomes

Funding Acknowledgement

Type of funding source: None

OP0306 CD11C-SPECIFIC ABLATION OF SHP1 INDUCES AUTOIMMUNE SIALADENITIS SIMILAR TO SJÖGREN’S SYNDROME

Background:

Dendritic cells (DCs) play important roles in inducing immune response as well as maintaining immune tolerance. Src homology 2 domain-containing protein tyrosine phosphatase-1 (Shp1) is a negative regulator of signaling in hematopoietic cells and is expressed in a variety of immune cells including DCs. Shp1 homozygous mutant mice (motheaten mice) develop multiple immunological abnormalities and they die around four weeks after birth because of severe pneumonitis. Motheaten mice produce large amounts of autoantibodies, and besides, B-1a cells, a distinct B cell subset, which are an important source of autoantibodies increase in these mice. The functional abnormality of DCs in motheaten mice has not been characterized, but DCs and macrophages increase in various organs of motheaten mice.

To analyze the function of Shp1 in DCs, we generated Shp1 conditional knockout mice (Shp1 CKO) in whichShp1gene is specifically depleted in CD11c+cells. We found that aged shp1 CKO developed autoimmune glomerulonephritis. We also found that they developed severe tubulointerstitial nephritis (TIN) at the age of 40 weeks, which is characterized by the infiltration of CD11c+and F4/80+cells. CD4+T cells from Shp1 CKO produce much more amount of IFNγ. Collectively, Shp1 in DCs acts as a key regulatory molecule to protect against autoimmunity.

Objectives:

We analyzed salivary glands of CKO to confirm whether they have autoimmune sialadenitis because TIN is known to be the most common renal manifestations of Sjögren’s syndrome in human.

Methods:

Shp1 CKO are generated by crossing a mouse line carrying floxedShp1allele to mice expressing Cre recombinase under the control of the CD11c promoter. Sex- and age-matchedPtpn6fl/fllittermates withoutCregene were studied as controls. We analyzed secretory function of the salivary glands in response to pilocarpine stimulation in Shp1 CKO at the age of 40 weeks or older. We then performed histological examination of salivary glands (submandibular glands and sublingual glands) with light-microscopy and immunohistochemical staining. The mononuclear cells prepared from the salivary glands were analyzed by flow cytometry (FCM). We also quantified anti-SSA/Ro60 antibodies and anti-SSB/LA antibodies by ELISA.

Results:

Shp1 CKO secreted less saliva flow compared to control mice by pilocarpine stimulation. Histological study showed Shp1 CKO exhibited massive infiltration of inflammatory cells in salivary glands associated with periductal foci and periductal fibrosis. Most of infiltrated cells were stained by anti- CD4 or B220 mAbs. FCM revealed that B cells increased in the salivary glands of Shp1 CKO. In addition, B-1a cells also increased in the salivary glands of the mice. The levels of anti-SSA/Ro60 antibodies and anti-SSB/LA antibodies were increased in Shp1 CKO.

Conclusion:

CD11c-specific ablation of Shp1 induces the ectopic generation of lymphoid structure in salivary glands and impairment of salivary secretion. Autoantibody profile in Shp1 CKO resembled that in human Sjögren’s syndrome. Our findings suggest that aged Shp1 CKO have the potential to become a new mouse model for the analysis of Sjögren’s syndrome.

References:

[1]Green C. M. et al. J Heredity. 1975; 250-258.

[2]Kaneko T. et al. J Immunology. 2012; 5397-540.

[3]Watanabe M. et al. Biochem Biophys Rep. in press.

Disclosure of Interests:

Masato Kinoshita: None declared, Yoriaki Kaneko Grant/research support from: CHUGAI PHARMACEUTICAL CO., LTD.

Astellas Pharma Inc.b, Speakers bureau: CHUGAI PHARMACEUTICAL CO., LTD.

Astellas Pharma Inc., Mitsuharu Watanabe: None declared, Yoichi Imai: None declared, Shreya Shrestha: None declared, Junya Suwa: None declared, Yuko Ohishi: None declared, Hiroko Hamatani: None declared, Masao Nakasatomi: None declared, Toru Sakairi: None declared, Hidekazu Ikeuchi Speakers bureau: CHUGAI PHARMACEUTICAL CO., LTD.

Astellas Pharma Inc., Yoshihisa Nojima: None declared, Keiju Hiromura Grant/research support from: CHUGAI PHARMACEUTICAL CO., LTD.

Astellas Pharma Inc., Speakers bureau: CHUGAI PHARMACEUTICAL CO., LTD.

Astellas Pharma Inc.

The association between 11C-methionine uptake, IDH gene mutation, and MGMT promoter methylation in patients with grade II and III gliomas

AIM

To evaluate the association between ¹¹C-methionine positron-emission tomography (¹¹C-methionine PET) findings, isocitrate dehydrogenase (IDH) gene mutation, and O⁶-methylguanine-DNA methyltransferase (MGMT) promoter methylation in patients with grade II and III gliomas.

MATERIALS AND METHODS

Data were collected from 40 patients with grade II and III gliomas who underwent both magnetic resonance imaging (MRI) and ¹¹C-methionine PET as part of their pre-surgical examination. IDH mutation was examined via DNA sequencing, and MGMT promoter methylation via quantitative methylation-specific polymerase chain reaction (PCR).

RESULTS

A threshold of MGMT promoter methylation of 1% was significantly associated with tumour/normal tissue (T/N) ratio. The T/N ratio in samples with MGMT promoter methylation ≥1% was higher than that in samples with MGMT promoter methylation <1%, and the difference was statistically significant (p=0.011). Reliable prediction of MGMT promoter methylation (<1% versus ≥1%) was possible using the T/N ratio under the receiver operator characteristic (ROC) curve with a sensitivity and specificity of 75% each (cut-off value=1.6: p=0.0226, area under the ROC curve [AUC]=0.76172). Conversely, the T/N ratio had no association with IDH mutation (p=0.6). The ROC curve revealed no reliable prediction of IDH mutation using the T/N ratio (p=0.606, AUC=0.60577).

CONCLUSION

¹¹C-methionine PET parameters can predict MGMT promoter methylation but not IDH mutation status. ¹¹C-methionine uptake may have limited potential to reflect DNA methylation processes in grade II and III gliomas.

P2458Restricted left atrial motion as a result of atrial stiffening in patients with cardiac amyloidosis

Background

Left atrial (LA) involvement of abnormal amyloid fibrils could induce LA dysfunction and stiffening in patients with cardiac amyloidosis (CA). Thus, the assessments of LA function and stiffness might be a potential approach to diagnose CA phenotype among patients with hypertrophied hearts.

Purpose

We sought to determine whether LA reservoir strain with speckle tracking echocardiography could be used a marker of LA stiffness in a derivation cohort. Furthermore, we tested to our hypothesis that LA reservoir strain could differentiate CA patients from hypertrophic cardiomyopathy (HCM) in an independent validation cohort.

Methods

In the derivation cohort, echocardiography was performed simultaneously with measurements of pulmonary capillary wedge pressure (PCWP) in 50 patients with suspected or established heart failure and relatively preserved left ventricular (LV) ejection fraction (56±10%). LA maximum and minimum volume index, and reservoir strain were measured from apical four-chamber view. LA stiffness index was computed as a pressure rise from x-trough to v-wave divided by an increase from minimum to maximum indexed LA volume (Figure A). In an independent validation group, we studied a total of 33 biopsy-proved CA patients and 127 HCM patients (LV ejection fraction: 57±11% vs. 66±10%, P<0.01) in sinus rhythm on the date of comprehensive echocardiographic study. Among them, cardiac magnetic resonance imaging (CMR) could be evaluated in 17 CA patients and 98 HCM patients. Furthermore, right heart catheterization was performed with 12 CA patients and 12 HCM patients in the CMR group.

Results

The derivation cohort study found that there was a significant curvilinear correlation of LA reservoir strain to LA stiffness index (Figure B). In the validation cohort, LA reservoir strain was reduced in patients with CA compared with HCM in all participants (11.6±5.6% vs. 18.5±6.9%, P<0.01), although there was no significant difference of LA maximal volume index between 2 groups (37±16 ml/m2 vs. 37±12 ml/m2, p=0.89). In the CMR group, the late gadolinium enhancement was observed in the LA wall in 16 patients with CA (94.1%) as shown in Figure C. In contrast, the LA enhancement revealed only in 1 patient with HCM (1.0%). Among patients with invasive measures, LA stiffness index [median (interquartile range)] was higher in patients with CA than that in patients with HCM [1.1 (0.4–2.8) vs. 0.2 (0.1–0.6), P=0.01].

Conclusions

LA reservoir function was fairly limited in patients with CA compared with HCM. Restricted LA motion might be related to atrial amyloid deposits or fibrosis, which potentially provokes atrial chamber stiffening.

Effects of Nicorandil Versus Nitroglycerin on Arterial Oxygenation During Two-Lung Ventilation and One-Lung Ventilation in Patients With Risk Factors for Myocardial Ischemia: A Prospective, Randomized, Double-Blind Study

OBJECTIVES

To compare the effects of nicorandil and nitroglycerin on arterial oxygenation during two-lung ventilation (TLV) and one-lung ventilation (OLV) in patients with risk factors for myocardial ischemia.

DESIGN

A prospective, randomized, double-blind study.

SETTING

A tertiary care hospital.

PARTICIPANTS

Fifty-six patients scheduled for elective video-assisted thoracic surgery were assigned randomly to either the nicorandil group or the nitroglycerin group.

INTERVENTIONS

Patients in the nicorandil group received a bolus dose of nicorandil, 0.08 mg/kg during induction of anesthesia, followed by a continuous infusion at a rate of 0.08 mg/kg/h. Patients in the nitroglycerin group received a continuous infusion of nitroglycerin at a rate of 1 µg/kg/min from the induction of anesthesia.

MEASUREMENTS AND MAIN RESULTS

Arterial blood gas analysis was performed at the following points: before induction of anesthesia; during TLV; at 5, 10, 20, and 30 minutes after the initiation of OLV. PaO₂ at TLV (479.7 ± 57.1 v 408.2 ± 70.9 mmHg, p < 0.001); and at 5 minutes (344.8 ± 85.1 v 282.6 ± 85.8 mmHg, p = 0.012), 20 minutes (215.7 ± 103.0 v 158.2 ± 74.5 mmHg, p = 0.027), and 30 minutes (198.8 ± 103.5 v 147.5 ± 64.1 mmHg, p = 0.039) after OLV was significantly higher in the nicorandil group than in the nitroglycerin group.

CONCLUSION

This study demonstrated that oxygenation during TLV and OLV was significantly higher in patients receiving nicorandil than in those receiving nitroglycerin.

Prerequisites to Salvage Profound Biventricular Failure Patients with Ventricular Assist Devices

We conducted chronic experiments to determine how to treat profound biventricular failure systematically with ventricular assist devices (VADs) and to analyze the factors that affect prognoses for this condition. Anoxic arrest was induced in ten goats by aortic cross-clamping under normothermic conditions (38.5° C) for 30 (n= 3), 45 (n= 1), and 60 (n= 6) minutes. A left ventricular assist device (LVAD) was implanted in eight animals, and a biventricular assist device (BVAD) was used in two. Three goats — two of which had undergone anoxic arrest for 30 minutes and one for 60 minutes — whose right atrial pressure (RAP) was approximately 18 mm Hg during the acute stage, recovered in two to three weeks, and the pumps were successfully removed. Pathological findings in these animals showed scattered areas of surviving myocardium, with connective tissue replacing the degenerated myocardium. The remaining five LVAD goats required higher RAPs to maintain circulation and died from various causes. Maintaining circulation without volume loading, even in the presence of arrhythmias, was easier with the BVAD. One BVAD animal that underwent 45 minutes of anoxic arrest recovered from right ventricular failure, and the right pump was removed. The second goat (anoxic arrest, 60 min) on the BVAD failed to recover. Autopsy of the myocardium revealed a thin ventricular wall. Our studies show that the use of VADs allows time for a failing heart to recover, but the potential for healing is affected by the severity of myocardial damage prior to VAD application. We believe that although LVADs can maintain circulation with high RAPs, the use of BVADs might be more beneficial for maintaining systemic organ function in cases of persistent biventricular failure.

Treatment of Acute Myocardial Infarction with Cardiogenic Shock using Left Ventricular Assist Device

We have treated ten cardiogenic shock patients after acute myocardial infarction (AMI) with a left ventricular assist device (LVAD). These patients were later divided into three groups: the first group with ventricular septal perforation, the second with aorto-coronary bypass grafting (ACBG) before LVAD implantation and the third group without ACBG. LVAD maintained the systemic circulation in each group, and cardiac function recovered enough to remove LVAD in 70% of the total patients. Two of three patients in the first group were discharged from hospital. Two weaned cases in the second group died of multiple organ failure and one was discharged, and hemorrhagic necrosis was seen in the bypassed area of the myocardium. One patient of the third group could not be weaned from LVAD because of respiratory failure though his heart function began to recover. Another case in the third group underwent bypass grafting after removal of LVAD. However ACBG surgery should be done very carefully because a patient in shock is occasionally intolerant to major surgery. In all groups, the major cause of death was multiple organ failure which was probably caused by the prolonged low output condition prior to LVAD application. In the light of this experience, it appears that LVAD should be applied before irreversible damage occurs to major organs, including the heart itself. To ensure the timely application of LVAD, some way must be found to introduce systematic application of LVAD into the normal course of AMI treatment.

Telomere length determined by the fluorescence in situ hybridisation distinguishes malignant and benign cells in cytological specimens

BACKGROUND

Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.

METHODS

Aspiration samples (n = 41) were smeared on glass slides and used for FISH.

RESULTS

Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound-guided FNA samples from the pancreas (n = 18).

CONCLUSIONS

The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients.

Diagnostic Accuracy of Neuroimaging to Delineate Diffuse Gliomas within the Brain: A Meta-Analysis

BACKGROUND

Brain imaging in diffuse glioma is used for diagnosis, treatment planning, and follow-up.

PURPOSE

In this meta-analysis, we address the diagnostic accuracy of imaging to delineate diffuse glioma.

DATA SOURCES

We systematically searched studies of adults with diffuse gliomas and correlation of imaging with histopathology.

STUDY SELECTION

Study inclusion was based on quality criteria. Individual patient data were used, if available.

DATA ANALYSIS

A hierarchic summary receiver operating characteristic method was applied. Low- and high-grade gliomas were analyzed in subgroups.

DATA SYNTHESIS

Sixty-one studies described 3532 samples in 1309 patients. The mean Standard for Reporting of Diagnostic Accuracy score (13/25) indicated suboptimal reporting quality. For diffuse gliomas as a whole, the diagnostic accuracy was best with T2-weighted imaging, measured as area under the curve, false-positive rate, true-positive rate, and diagnostic odds ratio of 95.6%, 3.3%, 82%, and 152. For low-grade gliomas, the diagnostic accuracy of T2-weighted imaging as a reference was 89.0%, 0.4%, 44.7%, and 205; and for high-grade gliomas, with T1-weighted gadolinium-enhanced MR imaging as a reference, it was 80.7%, 16.8%, 73.3%, and 14.8. In high-grade gliomas, MR spectroscopy (85.7%, 35.0%, 85.7%, and 12.4) and ¹¹C methionine-PET (85.1%, 38.7%, 93.7%, and 26.6) performed better than the reference imaging.

LIMITATIONS

True-negative samples were underrepresented in these data, so false-positive rates are probably less reliable than true-positive rates. Multimodality imaging data were unavailable.

CONCLUSIONS

The diagnostic accuracy of commonly used imaging is better for delineation of low-grade gliomas than high-grade gliomas on the basis of limited evidence. Improvement is indicated from advanced techniques, such as MR spectroscopy and PET.

Cytological diagnostic clues in poorly differentiated squamous cell carcinomas of the breast: Streaming arrangement, necrotic background, nucleolar enlargement and cannibalism of cancer cells

OBJECTIVE

Squamous cell carcinoma (SCC) is a rare histological type of breast cancer. The cytological diagnosis of non-keratinising, poorly differentiated SCC is often difficult, and distinguishing it from invasive ductal carcinoma or apocrine carcinoma (AC) is especially challenging. We aimed to define the diagnostic cytological features of poorly differentiated SCC of the breast.

METHODS

We studied the cytological findings of poorly differentiated SCC (n=10) and compared them to those of IDC (n=15) and AC (n=14). The following six cytological features were evaluated: streaming arrangement, nucleolar enlargement, dense nuclei, cannibalism, atypical keratinocytes and necrotic background.

RESULTS

SCC exhibited significantly higher frequencies of streaming arrangement (70% vs 6.7%, P=.002), nucleolar enlargement (80% vs 27%, P=.02), and necrotic background (80% vs 36%, P=.002) than invasive ductal carcinoma. The detection of two or three of these features yielded a higher sensitivity (80%) and specificity (93%) for the diagnosis of SCC. Streaming arrangement (70% vs 0%, P<.001), cannibalism (60% vs 0%, P=.002), and a necrotic background (80% vs 36%, P=.047) were all significantly more frequent in SCC than in AC. When distinguishing SCC from AC, the presence of two or three of these features yielded a high sensitivity (80%) and specificity (100%).

CONCLUSIONS

Cytological features such as a streaming arrangement, a necrotic background, nucleolar enlargement and cannibalism are useful indicators for the diagnosis of SCC of the breast. As such, greater attention should be paid to these morphological features in daily clinical practice.

Functional Anatomy of the Lateral Collateral Ligament Complex of the Elbow: Morphology and Strain

The anatomy of the lateral ulnar collateral ligament (LUCL) of the elbow was investigated in 26 fresh frozen cadavers. Two types of insertion of the LUCL were originally described but we found another type which is characterized by a broad single expansion along with a thin membranous fibre. Strain on the LUCL was measured in situ during extension and flexion with the forearm in supination, pronation and neutral. Strain in the proximal fibres started to occur at around 32° flexion and peaked at between 50° and 60° flexion. Strains measured in the distal fibres were smaller in magnitude. Forearm rotation had little effect on strain during extension to flexion. Based on these results, we conclude that the LUCL functions in unison with the annular ligament.

Magnetic Reversal of Electric Polarization with Fixed Chirality of Magnetic Structure in a Chiral-Lattice Helimagnet MnSb_{2}O_{6}

The correlation between magnetic and dielectric properties has been investigated for the single crystal of the chiral triangular-lattice helimagnet MnSb_{2}O_{6}. We found that the spin-spiral plane in the ground state has a considerable tilting from the (110) plane and that the sign of the spin-spiral tilting angle is coupled to the clockwise or counterclockwise manner of spin rotation and accordingly to the sign of magnetically induced electric polarization. This leads to unique magnetoelectric responses such as the magnetic-field-induced selection of a single ferroelectric domain as well as the reversal of electric polarization just by a slight tilting of the magnetic field direction, where the chiral nature of the crystal structure plays a crucial role through the coupling of the chirality between the crystal and magnetic structures. Our results demonstrate that crystallographic chirality can be an abundant source of novel magnetoelectric functions with coupled internal degrees of freedom.

Methods for immunoblot detection and electron microscopic localization of septin subunits in mammalian nervous systems

The minimal functional units of the mammalian septin system are diverse heterooligomers of SEPT1-14 subunits, which are most abundantly and differentially expressed in postmitotic neurons and glia. The subunit compositions of such heterooligomers are thought to differentiate their affinity for other proteins and lipids, and subcellular localization. Thus, high-precision quantification and mapping of each subunit is necessary to understand their subcellular functions and physiological roles. However, systematic information on the localization of individual septin subunits in the mammalian nervous system is limited. Here, we present our experimental workflows for the study of septin expression and localization in the rodent brain by immunoblot and serial section immunoelectron microscopy. Our protocols, based on standard methods, have been rigorously optimized and simplified for universality and reproducibility to aid non-experts in the field.

TORSADES DE POINTES ASSOCIATED WITH TAKOTSUBO CARDIOMYOPATHY IN AN ANOREXIA NERVOSA PATIENT DURING EMERGENCE FROM GENERAL ANESTHESIA

Takotsubo cardiomyopathy, also known as stress-induced cardiomyopathy, is a disease in which the patient exhibits transient, reversible left ventricular dysfunction that is triggered by physical or emotional stress. Prolongation of QT interval, a risk factor for arrhythmia and sudden death, has been reported to be prevalent among patients with Takotsubo cardiomyopathy and is also observed in those with severe anorexia nervosa. In this report, we describe the rare case of a 30-year-old female patient with anorexia nervosa who developed Torsades de Pointes associated with Takotsubo cardiomyopathy during emergence from general anesthesia for emergency exploratory laparotomy.

Polylactic acid nanosheets in prevention of postoperative intestinal adhesion and their effects on bacterial propagation in an experimental model

Background

Ultrathin films (nanosheets) adhere tightly to organ surfaces but prevent adhesion to other organs. The antiadhesive effect of nanosheets and their effect on bacterial propagation were investigated in a murine intestinal adhesion model.

Methods

Polylactic acid nanosheets (approximately 80 nm thick) were produced. Serosal defects were created by peeling off the intestinal serosa; these were left open or covered with nanosheets or Seprafilm® and the formation of intestinal adhesions was analysed. To examine bacterial propagation, a nanosheet or Seprafilm® was placed on intact murine jejunum followed by Escherichia coli inoculation at the site.

Results

Treatment both with nanosheets and with Seprafilm® reduced postoperative intestinal adhesion (mean adhesion score 0·67 for nanosheets, 0·43 for Seprafilm® and 2·87 for no antiadhesive treatment; P &lt; 0·001 for nanosheets or Seprafilm® versus no adhesive treatment). Nanosheet treatment did not affect bacterial propagation in the peritoneal cavity, whereas Seprafilm®-treated mice showed bacterial propagation, leading to increased mortality.

Conclusion

Nanosheets may be effective novel antiadhesive agents even in the presence of bacterial contamination. Surgical relevanceIntra-abdominal adhesions following surgical contamination can trigger postoperative complications and lead to deterioration in long-term quality of life. However, currently there are no effective antiadhesion materials to prevent the formation of adhesions.Treatment with ultrathin nanosheets effectively reduced postoperative intestinal adhesion in an experimental mouse model, and did not affect bacterial propagation in the peritoneal cavity.These nanosheets are potent novel antiadhesive materials that potentially can be applied even in contaminated conditions.