Effect of empagliflozin as add-on therapy on transtubular potassium concentration gradient in patients with type 2 diabetes hospitalized for acute decompensated heart failure

Background

The transtubular potassium concentration gradient (TTKG) has been reported to be a marker of renal aldosterone bioactivity, and has been shown to be a surrogate of arterial underfilling in patients with acute decompensated heart failure (ADHF). Moreover, high TTKG at discharge has been shown to be associated with poor prognosis in ADHF patients. Empagliflozin, one of the sodium glucose cotransporter 2 inhibitors, has been shown to reduce the risk of cardiovascular mortality in patients with type 2 diabetes mellitus (T2D) and cardiovascular disease. However, little is known about the effect of empagliflozin as add-on therapy on TTKG in T2D patients with ADHF.

Purpose

We sought to elucidate the effect of empagliflozin as add-on therapy on TTKG in T2D patients with ADHF.

Methods

We enrolled 58 consecutive T2D patients admitted for ADHF. On admission, enrolled patients were randomly assigned in a 1:1 ratio to either empagliflozin add-on therapy (EMPA(+)) or conventional glucose-lowering therapy (EMPA(−)). All patients in EMPA(+) group received empagliflozin (10 mg/day) throughout the study period. Left ventricular ejection fraction (LVEF) was measured at baseline using echocardiography. Body weight and vital signs, such as blood pressure and heart rate, were measured, and blood and urine samples were collected at baseline and 1, 2, 3 and 7 days after randomization. The TTKG was measured using the first morning urine samples collected on each day. TTKG was calculated according to the following equation: TTKG = (Ku/Ks)×(plasma osmolality/urine osmolality), where Ku is urine potassium concentration and Ks is serum potassium concentration, as previously reported.

Results

Thirty patients were assigned to the EMPA(+) group, and 28 patients were assigned to the EMPA(−) group. There were no significant baseline differences in LVEF, plasma B-type natriuretic peptide (BNP) level, body mass index, or serum creatinine level between the EMPA(+) and EMPA(−) groups. TTKG did not significantly differ between the two groups at baseline. However, seven days after randomization, plasma BNP level was significantly lower in the EMPA(+) group than in the EMPA(−) group (median 227 [IQR 114–381] pg/mL vs 362 [227–554] pg/mL, p=0.0294). Furthermore, TTKG of the EMPA(+) group was significantly lower at 2, 3 and 7 days after randomization (Figure).

Conclusions

This study demonstrated that empagliflozin as add-on therapy can lower TTKG in T2D patients with ADHF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Role of diuretics on long-term mortality may differ in volume status in patients with acute myocardial infarction

Background

Diuretics has been reported to have a potential for an activation of the renin-angiotensin-aldosterone system and the sympathetic nervous system, leading to a possibility of poor clinical outcome in patients with cardiovascular disease. However, few data are available on clinical impact of diuretics on long-term outcome in patients with acute myocardial infarction (AMI) based on plasma volume status.

Methods

To address the issue, a total of 3,416 survived patients with AMI who were registered to a large database of the Osaka Acute Coronary Insufficiency Study (OACIS) were studied. Plasma volume status was assessed with the estimated plasma volume status (ePVS) that was calculated at discharge as follows: actual PV = (1 − hematocrit) × [a + (b × body weight)] (a=1530 in males and a=864 in females, b=41.0 in males and b=47.9 in females); ideal PV = c × body weight (c=39 in males and c=40 in females), and ePVS = [(actual PV − ideal PV)/ideal PV] × 100 (%). Multivariable Cox regression analysis and propensity score matching were performed to account for imbalances in covariates. The endpoint was all-cause of death (ACD) within 5 years.

Results

During a median follow-up period of 855±656 days, 193 patients had ACD. In whole population, there was no significant difference in long-term mortality risk between patients with and without diuretics in both multivariate cox regression model and propensity score matching population. When patients were divided into 2 groups according to ePVS with a median value of 4.2%, 46 and 147 patients had ACD in groups with low ePVS and high ePVS, respectively. Multivariate Cox analysis showed that use of diuretics was independently associated with an increased risk of ACD in low ePVS group, (HR: 2.63, 95% confidence interval [CI]: 1.22–5.63, p=0.01), but not in high ePVS group (HR: 0.70, 95% CI: 0.44–1.10, p=0.12). These observations were consistent in the propensity-score matched cohorts; the 5-year mortality rate was significantly higher in patients with diuretics than those without among low ePVS group (4.7% vs 1.7%, p=0.041), but not among high ePVS group (8.0% vs 10.3%, p=0.247).

Conclusion

Prescription of diuretics at discharge was associated with increased risk of 5-year mortality in patients with AMI without PV expansion, but not with PV expansion. The role of diuretics on long-term mortality may differ in plasma volume status. Therefore, prescription of diuretics after AMI may be considered based on plasma volume status.

Funding Acknowledgement

Type of funding source: None

Usefulness of lead delivery catheter system for true right ventricular septal pacing

Background

Right ventricular (RV) septal pacing is often selected to preserve a more physiologic ventricular activation. But the pacing leads are not always located in true septal wall, rather in hinge or free wall in some cases with the conventional stylet-guided lead implantation. In recent years, new guiding catheter systems has attracted attention as a solution to that problem.

Objective

The aim of this study is to investigate that true ventricular sepal pacing can be achieved by use of the new guiding catheter system for pacing lead.

Methods

We enrolled 198 patients who underwent RV septal lead implantation and computed tomography (CT) after pacemaker implantation. 16 cases were used delivery catheter (Delivery), and 182 cases were used stylet for targeting ventricular septum (Conventional). We analyzed the lead locations with CT, and evaluated capture thresholds, R-wave amplitudes, lead impedances and 12-lead electrocardiogram findings one month after implantation.

Results

All cases of delivery catheter group had true septal lead positions (Delivery; 100% vs Conventional; 44%, p<0.01). Capture thresholds and lead impedances had not significant differences between between two groups (0.65±0.15V vs 0.60±0.15V, p=0.21, 570±95Ω vs 595±107Ω, p=0.39, respectively). R-wave amplitudes were significantly higher in delivery catheter group (13.0±4.8mV vs 10±4.6mV, p<0.01). Paced QRS durations were shorter in delivery catheter group (128±16ms vs 150±21ms, p<0.01).

Conclusions

The delivery catheter system designated for pacing lead can contribute to select the true ventricular septal sites and to attain the more physiologic ventricular activation.

Funding Acknowledgement

Type of funding source: None

Comparative prognostic impact of ACCI and AHEAD risk score in heart failure with reduced, mid-range and preserved left ventricular ejection fraction admitted for acute decompensated heart failure

Background

Comorbidities are strongly associated with poor clinical outcome in heart failure patients (pts). The Age-adjusted Charlson comorbidity index (ACCI), which is well-known widely used comorbidity index, recently has been used as a robust prognostic model in heart failure pts. On the other hand, AHEAD risk score has been recently reported as a useful long-term risk stratification score in acute decompensated heart failure (ADHF) pts. Recently, a new group of heart failure pts with mid-range ejection fraction (HFmrEF) has been defined, separated from reduced ejection fraction (HFrEF) and preserved ejection fraction (HFpEF). We sought to compare the prognostic value of ACCI and AHEAD score in ADHF pts, relating to HFrEF, HFmrEF and HFpEF.

Methods

We prospectively studied 410 consecutive ADHF pts (HFrEF [n=143], HFmrEF [n=99] and HFpEF [n=168]) with survival discharge. ACCI contains 19 issues which was weighted according to their potential influence on mortality. AHEAD risk score is a simple index, which is range 0–5; atrial fibrillation, hemoglobin <13 mg/dL for men and 12 mg/dL for women, age >70 years, creatinine >130 μmol/L, and diabetes mellitus. The endpoint of this study was all cause death (ACD).

Results

During a follow-up period of 2.4±1.4 years, 119 pts had ACD (42, 29 and 48 pts in HFrEF, HFmrEF and HFpEF, respectively). At univariate Cox analysis, ACCI and AHEAD risk score were significantly associated with ACD in each subgroup. At multivariate Cox analysis, in HFrEF pts, ACCI, but not AHEAD risk score, showed the significant and independent association with ACD. In HFmrEF, both ACCI and AHEAD risk score was significantly and independently associated with ACD and ROC analysis showed AUC of ACCI was greater than that of AHEAD risk score (0.778 [0.683–0.855] vs 0.637 [0.572–0.764], p=0.07). On the other hand, in HFpEF pts, AHEAD risk score, but not ACCI, showed the significant and independent association ACD.

Conclusion

ACCI provides more prognostic value in HFrEF pts, and AHEAD risk score has more prognostic value in HFpEF pts. In HFmrEF pts, both ACCI and AHEAD score might have prognostic values, although ACCI tends to be more associated with ACD than AHEAD score.

Funding Acknowledgement

Type of funding source: None

Prognostic significance of cardiac 123I-MIBG SPECT imaging in patients with acute decompensated heart failure with preserved left ventricular ejection fraction

Background

Cardiac sympathetic nerve dysfunction, which is assessed by I-123 metaiodobenzylguanidine (MIBG) imaging, is associated with the poor outcomes in patients with heart failure (HF). Most of the literature on the use of 123I-MIBG imaging is based on planar images in patients with chronic HF and reduced left ventricular ejection fraction (HFrEF), because It is technically challenging to conduct precise 123I-MIBG SPECT analysis in globally denervated heart, which is frequently observed in HFrEF patients. There was no information available on cardiac sympathetic nerve dysfunction evaluated by cardiac MIBG SPECT imaging in acute decompensated HF (ADHF) patients with preserved left ventricular ejection fraction (HFpEF).

Purpose

We aimed to clarify the prognostic significance of 123I-MIBG SPECT myocardial imaging in ADHF patients with HFpEF.

Methods

We enrolled 183 patients who were admitted for ADHF with HFpEF, discharged with survival. All patients underwent cardiac MIBG imaging at the timing of discharge. The cardiac MIBG heart to mediastinum ratio (H/M) was calculated on the early image and the delayed image (late H/M). We studied 156 patients after excluding 27 patients whose MIBG SPECT reconstruction was difficult due to too low MIBG uptake or extracardiac accumulation interference. SPECT analysis on the delayed image was conducted by using CardioBull, a fully automated software for the quantification of I-123 MIBG SPECT. All of 17 regional tracer uptake were compared with normal control database. A scoring algorithm for the evaluation of low uptake employs a 5-point scoring system as 0–4 for normal, mildly abnormal, moderately abnormal, severe abnormal, and perfusion defect, respectively. The summed severity (SSS) scores were obtained by summing the score for all segments. SSS could range from 0 to 68. The endpoint of this study is cardiac events defined as the composite of unplanned heart failure hospitalization and cardiac death.

Results

During a mean follow up period of 2.4±1.6 years, 60 patients reached cardiac events. SSS was significantly high in patients with than without cardiac events (20 [10–27] vs 7 [4–16], p<0.0001). SSS (p<0.0001) was significantly associated with cardiac events after multivariable Cox adjustment of age, sex, creatinine and log-transformed BNP level, although late H/M showed the significant association with the endpoint at the univariate Cox analysis. Kaplan-Meier analysis showed that patients with high SSS (>10, defined by median) had significantly greater risk of cardiac event (56% vs 21%, Hazard ratio: 3.56 (2.00–6.33, p<0.0001). ROC curve analysis showed that area under the curve (AUC) of SSS was 0.746 [95% CI:0.670, 0.812], which was significantly higher than that of late H/M (0.618 [95% CI:0.537, 0.695]) (p=0.0159).

Conclusion

Cardiac MIBG SPECT imaging was useful for risk stratification in ADHF patients with HFpEF.

Funding Acknowledgement

Type of funding source: None

Impact of comorbidity on the predictive value of cystatin-C in patients admitted for acute decompensated heart failure: insights from a prospective study

Background

Comorbidities are strongly associated with poor clinical outcome in heart failure patients. The Age-adjusted Charlson comorbidity index (ACCI), which is well-known widely used comorbidity index, recently has been used as a robust prognostic model in heart failure patients. On the other hand, Cystatin C, as a novel and important biomarker of renal function, has been recently reported as a useful long-term risk stratification score in heart failure patients. However, there is no information available on the impact of comorbidities on the prognostic value of cystatin-C in patients admitted for acute decompensated heart failure (ADHF).

Methods

We prospectively studied 458 consecutive ADHF patients with survival discharge. Patients with hemodialysis were excluded. Echocardiography and venous blood sampling were performed just before discharge and serum cystatin-C level was measured. Comorbidity was measured with the Age-adjusted Charlson comorbidity index (ACCI). ACCI was commonly used for the evaluation of the comorbid condition which is weighted and scored, with additional points added for age. The endpoint was all-cause death (ACD).

Results

During a follow-up period of 2.8±1.5 years, 132 patients had ACD. At multivariate Cox analysis, ACCI (p=0.0015) and cystatin-C level (p=0.0145) were significantly and independently associated with ACD. Patients with high ACCI (≥6: determined by ROC analysis) had a significantly greater risk of ACD (37.2% vs 17.8%, p<0.0001, HR 2.45 [1.61–3.70]). In the subgroup of higher ACCI, patients with higher cystatin-C level (≥1.56: determined by ROC analysis) had a significantly higher risk of ACD (50.3% vs 23.4%). Furthermore, in the subgroup of lower ACCI, patients with higher cystatin-C level had also significantly higher risk of ACD (34.2% vs 12.1%).

Conclusions

The prognostic value of cystatin-C is not affected by comorbidities and cystatin-C provide prognostic information even in patients admitted for ADHF, irrespective of comorbid burden.

All-cause death-free rate in ADHF pts

Funding Acknowledgement

Type of funding source: None

Prognostic value of nutritional status in patients with heart failure with preserved ejection fraction, with and without atrial fibrillation: insights From PURSUIT-HFpEF Registry

Background

Malnutrition is one of the most important comorbidities among heart failure (HF) patients, and serum cholinesterase (CHE) has been reported to be a prognostic factor in HF patients. On the other hand, atrial fibrillation (AF) is frequently observed in patients with HF with preserved ejection fraction (HFpEF). However, there is little information available on the prognostic value of nutritional status in HFpEF patients, with and without AF. We sought to clarify the prognostic value of CHE in HFpEF with and without AF and compare it with that of other nutrition indices such as gastric nutritional risk index (GNRI), controlling nutritional status (CONUT), and the prognostic nutritional index (PNI).

Methods and results

Patients data were extracted from The Prospective mUlticenteR obServational stUdy of patIenTs with Heart Failure with Preserved Ejection Fraction (PURSUIT HFpEF) study, which is a prospective multicenter observational registry for acute decompensated heart failure patients with left ventricular ejection fraction ≥50% in Osaka. We analyzed 380 patients (median age: 80 [75–87] years, male: 46%) after exclusion of patients with in-hospital death, missing follow-up data, or missing data to calculate nutritional indices. On admission, 155 patients had AF. Laboratory data were obtained at discharge. During a mean follow up period of 1.1±0.6 years, 131 patients had a composite endpoint (CE) of all-cause death and hospitalization for worsening heart failure or cerebrovascular disorder. In multivariate Cox analysis, in patients with AF, CHE was significantly associated with CE independently of age, gender and body mass index after the adjustment with serum albumin, total cholesterol levels and total lymphocyte count, while it was not significantly associated with CE in patients without AF. C-index of CHE (0.708) was higher than that of GNRI (0.555, p=0.0028), CONUT (0.651, p=0.208) and PNI (0.635, p=0.208) in AF patients, while there were no significant differences in those nutritional indices in patients without AF. Kaplan-Meier curve analysis revealed that AF patients with lower CHE (<208 U/L = median value) had higher risk of CE than those with higher CHE (44% vs 18%, adjusted HR 3.26 95% CI [1.66–6.67], p=0.0005), while there was no significant difference in the occurrence rate of CE between patients with and without higher CHE in non-AF group (42% vs 31%, adjusted HR 1.28 95% CI [0.78–2.13], p=0.33).

Conclusions

Prognostic value of CHE would be stronger than other nutritional indices in HFpEF patients with AF, while it would be weak in HFpEF patients without AF.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Roche Diagnostics K.K.; Fuji Film Toyama Chemical Co. Ltd.

Cardiac mitofusin-1 is declined in non-responding patients with idiopathic dilated cardiomyopathy

Background/Introduction

Mitochondria are dynamic regulators of cellular metabolism and homeostasis. The dysfunction of mitochondria has long been considered a major contributor to aging and age-related diseases. The prognosis of severe heart failure is still unacceptably poor and it is urgent to establish new therapies for this critical condition. Some patients with heart failure do not respond to established multidisciplinary treatment and they are classified as “non-responders”. The outcome is especially poor for non-responders, and underlying mechanisms are largely unknown.

Purpose

Studies indicate mitochondrial dysfunction has causal roles for metabolic remodeling in the failing heart, but underlying mechanisms remain to be explored. This study tried to elucidate the role of Mitofusin-1 in a failing heart.

Methods

We examined twenty-two heart failure patients who underwent endomyocardial biopsy of intraventricular septum. Patients were classified as non-responders when their left-ventricular (LV) ejection fraction did not show more than 10% improvement at remote phase after biopsy. Fourteen patients were classified as responders, and eight as non-responders. Electron microscopy, quantitative PCR, and immunofluorescence studies were performed to explore the biological processes or molecules involved in failure to respond. In addition to studies with cardiac tissue specific knockout mice, we also conducted functional in-vitro studies with neonatal rat ventricular myocytes.

Results

Twenty-two patients with IDCM who underwent endomyocardial biopsy were enrolled in this study, including 14 responders and 8 non-responders. Transmission electron microscopy (EM) showed a significant reduction in mitochondrial size in cardiomyocytes of non-responders compared to responders. Quantitative PCR revealed that transcript of mitochondrial fusion protein, Mitofusin-1, was significantly reduced in non-responders. Studies with neonatal rat ventricular myocytes (NRVMs) indicated that the beta-1 adrenergic receptor-mediated signaling pathway negatively regulates Mitofusin-1 expression. Suppression of Mitofusin-1 resulted in a significant reduction in mitochondrial respiration of NRVMs. We generated left ventricular pressure overload model with thoracic aortic constriction (TAC) in cardiac specific Mitofusin-1 knockout model (c-Mfn1 KO). Systolic function was reduced in c-Mfn1 KO mice, and EM study showed an increase in dysfunctional mitochondria in the KO group subjected to TAC.

Conclusions

Mitofusin-1 becomes a biomarker for non-responders with heart failure. In addition, our results suggest that therapies targeting mitochondrial dynamics and homeostasis would become next generation therapy for severe heart failure patients.

Funding Acknowledgement

Type of funding source: None

Delayed hyperenhancement obtained by non-contrast computed tomography following coronary angiography in patients of extracorporeal cardiopulmonary resuscitation

Background/Introduction

Extracorporeal cardiopulmonary resuscitation (ECPR) has been reported to improve survival and neurologic outcome as compared to conventional CPR in refractory cardiac arrest. Although prognostic factors of these patients have been reported, predicting of outcome is difficult in real world. Recently, early evaluation of myocardial viability in acute myocardial infarction by non-contrast computed tomography (CT) post coronary angiography (CAG) has been reported. And myocardial contrast delayed enhancement obtained by this method related to higher risk of cardiac events. However, few studies have reported delayed enhancement on left ventricular wall findings in non-contrast CT after CAG in terms of patients performed ECPR.

Purpose

To investigate the impact of delayed hyperenhancement obtained by non-contrast CT following CAG in patients performed ECPR.

Methods

We investigated 79 patients treated by ECPR for refractory cardiac arrest regardless of whether in-hospital or out-hospital in our institute from Apr 2009 to Feb 2018. Thirty-two in these patients received non-contrast CT following CAG with ECPR were enrolled. All ECPR cases underwent VA-ECMO in the catheter laboratory using percutaneous procedure while maintaining conventional CPR. Non-ECG-gated and non-contrast CT was performed using a 64-row multidetector CT scanner.

Results

Survival rate was 18.8% in this cohort. There was no significant difference between survive and in-hospital death group in terms of patient characteristics, clinical time courses, initial blood samples and procedure characteristics. Only delayed hyperenhancement showed significant difference between 2 groups (p=0.04). All delayed hyperenhancements were detected in only in-hospital death group. Delayed hyperenhancement was detected in 12 cases (37.5%). Initial shockable rhythm was less common in cases with delayed hyperenhancement. Cardiac death tended to be more frequent in patients with delayed hyperenhancement. The major causes of death were bleeding (41.7%) and heart failure (33%).

Conclusion(s)

Delayed hyperenhancement in patients treated ECPR was strong predictor of in-hospital death.

Image of delayed hyperenhancement

Funding Acknowledgement

Type of funding source: None

Long-term serial changes of cardiac sympathetic nerve dysfunction in acute decompensated heart failure patients with reduced, mid-range and preserved left ventricular ejection fraction

Background

Cardiac sympathetic nerve dysfunction, which is assessed by I-123 metaiodobenzylguanidine (MIBG) imaging, is associated with the poor outcomes in patients with chronic heart failure (CHF). Serial evaluation of cardiac MIBG imaging was shown to be useful for predicting adverse outcome in CHF. However, there was no information available on long-term serial changes of cardiac sympathetic nerve dysfunction after discharge of acute decompensated heart failure (ADHF) hospitalization.

Purpose

We aimed to clarify the serial change of cardiac MIBG imaging parameter in long-term after discharge of heart failure hospitalization, especially relating to HFrEF (LVEF<40%), HFmrEF (40%≤LVEF<50%) and HFpEF (LVEF≥50%).

Methods

We studied 112 patients (HFrEF; n=44, HFmrEF; n=23 and HFpEF; n=45) who were admitted for ADHF, discharged with survival and without heart failure hospitalization during follow-up period. All patients underwent cardiac MIBG imaging at the timing of discharge, in 6–12 months and in 18–24 months after discharge. The cardiac MIBG heart to mediastinum ratio (H/M) was calculated on the early image and the delayed image (late H/M). The cardiac MIBG washout rate (WR) was calculated from the early and delayed planar images after taking radioactive decay of I-123 into consideration.

Results

In HFrEF patients, late H/M was significantly improved from discharge to 6–12 months data (1.60±0.24 vs 1.75±0.31, p<0.0001). Late H/M of HFmrEF patients was also significantly improved from discharge to 18–24 months data (1.71±0.27 vs 1.84±0.29 p=0.043). On the other hand, late H/M of HFpEF patients was not significantly changed. As for WR, WR in HFrEF and HFmrEF patients was significantly improved from discharge to 18–24 months data, although WR of HFpEF was not significantly changed.

Conclusion

The improvement in cardiac sympathetic nerve dysfunction was observed in patients with HFrEF and HFmrEF, not in HFpEF, after the discharge of acute heart failure hospitalization.

Funding Acknowledgement

Type of funding source: None

Long-term prognostic value of the combination of malnutrition and pulmonary-systemic pressure ratio in patients admitted with acute decompensated heart failure

Background

Malnutrition is associated with increased mortality risk in patients (pts) with acute decompensated heart failure (ADHF). On the other hand, concomitant presence of pulmonary hypertension in heart failure is associated with increased adverse events and may be related to interventricular uncoupling and impaired cardiac efficiency. It has recently been shown that an increased mean pulmonary artery pressure to mean systemic arterial pressure ratio (MPS ratio), a marker of interventricular coupling and efficiency, is associated with worse clinical outcomes in patients with advanced heart failure. However, there is no information available on the long-term prognostic value of the combination of malnutrition and MPS ratio in pts admitted for ADHF.

Methods and results

We studied 248 pts admitted for ADHF, who underwent right heart catheterization at the admission and were discharged with survival. Malnutrition was assessed by geriatric nutritional risk index (GNRI), prognostic nutritional index (PNI) and controlling nutritional status score (CONUT). During a mean follow-up period of 5.2±4.4 yrs, 62 pts had cardiovascular death (CVD). MPS ratio was significantly greater in pts with than without CVD (0.408±0.114 vs 0.347±0.102, p=0.0001). GNRI and PNI were significantly lower, CONUT was significantly greater in pts with than without CVD. At multivariate Cox regression analysis, GNRI and MPS ratio were significantly associated with CVD, independently of prior heart failure hospitalization, eGFR, and serum sodium level and anemia, although PNI and CONUT showed the association with CVD at unvariate analysis. Pts with malnutrition (GNRI≤median value=96.5) and greater MPS ratio (≥median value=0.346) had a significantly higher CVD risk than those with either and none of them (51% vs 20% vs 12%, p<0.0001, respectively).

Conclusions

The combination of malnutrition and MPS ratio might be useful for stratifying pts at risk for CVD in patients with ADHF.

Funding Acknowledgement

Type of funding source: None

Gut microbiome alterations in type 1 autoimmune pancreatitis after induction of remission by prednisolone

Although increasing evidence demonstrates the association between intestinal dysbiosis and pancreatic diseases such as chronic pancreatitis and pancreatic cancer, it remains largely unknown whether intestinal dysbiosis is involved in the immunopathogenesis of autoimmune pancreatitis (AIP). Recently, we found that intestinal dysbiosis mediates experimental AIP via the activation of plasmacytoid dendritic cells (pDCs), which can produce interferon (IFN)-α and interleukin (IL)-33. However, candidate intestinal bacteria, which promote the development of AIP, have not been identified. Fecal samples were obtained from type 1 AIP patients before and after prednisolone (PSL) treatment and subjected to 16S ribosomal RNA sequencing to evaluate the composition of intestinal bacteria. Induction of remission by PSL was associated with the complete disappearance of Klebsiella species from feces in two of the three analyzed patients with type 1 AIP. To assess the pathogenicity of Klebsiella species, mild experimental AIP was induced in MRL/MpJ mice by repeated injections of 10 μg of polyinosinic-polycytidylic acid [poly(I:C)], in combination with oral administration of heat-killed Klebsiella pneumoniae. The AIP pathology score was significantly higher in MRL/MpJ mice that received both oral administration of heat-killed K. pneumoniae and intraperitoneal injections of poly(I:C) than in those administered either agent alone. Pancreatic accumulation of pDCs capable of producing large amounts of IFN-α and IL-33 was also significantly higher in mice that received both treatments. These data suggest that intestinal colonization by K. pneumoniae may play an intensifying role in the development of type 1 AIP.

Vertical and horizontal distributions of 137Cs on paved surfaces affected by the Fukushima Dai-ichi Nuclear Power Plant accident

Vertical and horizontal distributions are fundamental for sampling and in-situ gamma spectrum measurement strategies. The distributions of ¹³⁷Cs were investigated for paved surfaces affected by the Fukusima Dai-ichi Nuclear Power Plant accident. Additionally, the effects of the distributions on the measurement uncertainties of in-situ spectrometry were evaluated. Relaxation mass depth, representing the depth profile of ¹³⁷Cs, was estimated to be less than 0.23 g cm^-2. Variation in the relaxation mass depth, of 0.1-0.23 g cm^-2, led to a minor error (less than 5%) in the spectral analysis of the¹³⁷Cs inventory (activity per unit area, kBq m^-2). The ¹³⁷Cs inventory, within a 20 × 20 m square of 400 cells each measuring 1 m², showed an uneven distribution with large variation; coefficient of variation ranged from 54 to 136% of geometric average inventory of 424 kBq m^-2. Increasing the grid size decreased ¹³⁷Cs inventory variation among cells, revealing the relationship between instrument field of view and the spatial uncertainty of the results of in-situ gamma spectrometry.

Combined Atomic Force Microscope and Volumetric Light Sheet System for Correlative Force and Fluorescence Mechanobiology Studies

The central goals of mechanobiology are to understand how cells generate force and how they respond to environmental mechanical stimuli. A full picture of these processes requires high-resolution, volumetric imaging with time-correlated force measurements. Here we present an instrument that combines an open-top, single-objective light sheet fluorescence microscope with an atomic force microscope (AFM), providing simultaneous volumetric imaging with high spatiotemporal resolution and high dynamic range force capability (10 pN - 100 nN). With this system we have captured lysosome trafficking, vimentin nuclear caging, and actin dynamics on the order of one second per single-cell volume. To showcase the unique advantages of combining Line Bessel light sheet imaging with AFM, we measured the forces exerted by a macrophage during FcɣR-mediated phagocytosis while performing both sequential two-color, fixed plane and volumetric imaging of F-actin. This unique instrument allows for a myriad of novel studies investigating the coupling of cellular dynamics and mechanical forces.