The effects of 18-h fasting with low-carbohydrate diet preparation on suppressed physiological myocardial (18)F-fluorodeoxyglucose (FDG) uptake and possible minimal effects of unfractionated heparin use in patients with suspected cardiac involvement sarcoidosis.

BACKGROUND: (18)F-fluorodeoxyglucose (FDG) PET plays an important role in the detection of cardiac involvement sarcoidosis (CS). However, diffuse left ventricle (LV) wall uptake sometimes makes it difficult to distinguish between positive uptake and physiological uptake. The aims of this study were to evaluate the effects of 18-h fasting with low-carbohydrate diet (LCD) vs a minimum of 6-h fasting preparations on diffuse LV FDG uptake and free fatty acid (FFA) levels in patients with suspected CS. METHODS: Eighty-two patients with suspected CS were divided into 2 preparation protocols: one with a minimum 6-h fast without LCD preparation (group A, n = 58) and the other with a minimum 18-h fast with LCD preparation (group B, n = 24). All patients also received intravenous unfractionated heparin (UFH; 50 IU/kg) before the injection of FDG. RESULTS: Group A showed a higher percentage of diffuse LV uptake than did group B (27.6 vs 0.0%, P = .0041). Group B showed higher FFA levels (1159.1 ± 393.0, 650.5 ± 310.9 µEq/L, P < .0001) than did group A. Patients with diffuse LV uptake (n = 16) showed lower FFA levels than did other patients (n = 66) (432.1 ± 296.1, 888.4 ± 381.4 µEq/L, P < .0001). UFH administration significantly increased FFAs in both groups, even in the patients with diffuse LV FDG uptake. CONCLUSIONS: The 18-h fast with LCD preparation significantly reduced diffuse LV uptake and increased FFA levels. In particular, the FFA level was significantly lower in patients with LV diffuse uptake than in patients without LV diffuse uptake. Acutely increasing plasma FFA through the use of UFH may not have a significant role in reducing physiological LV FDG uptake.

Cellular memory function from 3D to 2D: Three-dimensional high density collagen microfiber cultures induce their resistance to reactive oxygen species.

Cell properties generally change when the culture condition is changed. However, mesenchymal stem cells cultured on a hard material surface maintain their differentiation characteristics even after being cultured on a soft material surface. This phenomenon suggests the possibility of a cell culture material to memorize stem cell function even in changing cell culture conditions. However, there are no reports about cell memory function in three-dimensional (3D) culture. In this study, colon cancer cells were cultured with collagen microfibers (CMF) in 3D to evaluate their resistance to reactive oxygen species (ROS) in comparison with a monolayer (2D) culture condition and to understand the effect of 3D-culture on cell memory function. The ratio of ROS-negative cancer cells in 3D culture increased with increasing amounts of CMF and the highest amount of CMF was revealed to be 35-fold higher than that of the 2D condition. The ROS-negative cells ratio was maintained for 7 days after re-seeding in a 2D culture condition, suggesting a 3D-memory function of ROS resistance. The findings of this study will open up new opportunities for 3D culture to induce cell memory function.

In vitro throughput screening of anticancer drugs using patient-derived cell lines cultured on vascularized three-dimensional stromal tissues.

The development of high-throughput anticancer drug screening methods using patient-derived cancer cell (PDC) lines that maintain their original characteristics in an in vitro three-dimensional (3D) culture system poses a significant challenge to achieving personalized cancer medicine. Because stromal tissue plays a critical role in the composition and maintenance of the cancer microenvironment, in vitro 3D-culture using reconstructed stromal tissues has attracted considerable attention. Here, a simple and unique in vitro 3D-culture method using heparin and collagen together with fibroblasts and endothelial cells to fabricate vascularized 3D-stromal tissues for in vitro culture of PDCs is reported. Whereas co-treatment with bevacizumab, a monoclonal antibody against vascular endothelial growth factor, and 5-fluorouracil significantly reduced the survival rate of 3D-cultured PDCs to 30%, separate addition of each drug did not induce comparable strong cytotoxicity, suggesting the possibility of evaluating the combined effect of anticancer drugs and angiogenesis inhibitors. Surprisingly, drug evaluation using eight PDC lines with the 3D-culture method resulted in a drug efficacy concordance rate of 75% with clinical outcomes. The model is expected to be applicable to in vitro throughput drug screening for the development of personalized cancer medicine. STATEMENT OF SIGNIFICANCE: To replicate the cancer microenvironment, we constructed a cancer-stromal tissue model in which cancer cells are placed above and inside stromal tissue with vascular network structures derived from vascular endothelial cells in fibroblast tissue using CAViTs method. Using this method, we were able to reproduce the invasion and metastasis processes of cancer cells observed in vivo. Using patient-derived cancer cells, we assessed the possibility of evaluating the combined effect with an angiogenesis inhibitor. Further, primary cancer cells also grew on the stromal tissues with the normal medium. These data suggest that the model may be useful for new in vitro drug screening and personalized cancer medicine.

Details of the ultrafast DNA photo-cross-linking reaction of 3-cyanovinylcarbazole nucleoside: cis-trans isomeric effect and the application for SNP-based genotyping.

To clarify the cis-trans isomeric effect on the ultrafast DNA photo-cross-linking reaction of 3-cyanovinylcarbazole nucleoside ((CNV)K) in the DNA duplex, which gives a single photodimer on the reversed-phase HPLC chromatogram, the kinetics of the cis-trans photoisomerization of (CNV)K in double-stranded DNA was evaluated. Since the photoisomerization rate constant for cis to trans isomerization in double-stranded DNA was significantly larger than that for trans to cis isomerization, and the thermodynamic stability of the trans isomer was higher than that of the cis isomer, it was strongly suggested that the trans isomer of (CNV)K is a reactive species of the photo-cross-linking reaction. (1)H-(1)H NOESY analysis of the photoadduct consisting of (CNV)K and T also supported the trans-mediated photo-cross-linking reaction of (CNV)K. By using this ultrafast photo-cross-linking reaction for the molecular beacon-based SNPs typing, four individual Japanese rice strains were clearly distinguishable with simple photoirradiation and fluorescence imaging using double-stranded target DNAs.

A Solution Kinetics Simulation Method for Conventional and Selective Plasma Exchange Using a Complete Mixed Reactor Model.

At present, conventional plasma exchange (CPE) sets removal rate, replacement fluid volume and replacement fluid albumin (Alb) concentration according to the first-order kinetics of mass balance for removal of pathogenic substances. With the spread of selective plasma exchange (SePE), it has become necessary to set the removal rate and replacement fluid Alb concentration based on the initial concentration for each performance of the plasma separator. Considering the patient as a single reactor we devised a complete mixed reactor model simulating the concentration change in the reactor. Our formula is obtained by adding membrane performance and replacement fluid concentration to formulas currently available and can be used for both CPE and SePE. For the in vitro experiment, fresh frozen plasma stored in a bag was used to simulate a patient's circulating plasma. Plasma was separated by plasma separator Evacure EC-4A10 (EC-4A) (Kawasumi Laboratories Inc., Tokyo, Japan) while a replacement Alb solution was simultaneously entered into the circuit at the same rate as separation. IgG, Alb, total protein (TP), and fibrinogen (Fib) concentrations were measured every 10 min and examined for correlation with the value predicted by the mass balance formula. The concentration of each solute was measured 21 times during the 195 min of the experiment. The rate of change of each solute was IgG 76%, Alb 58%, TP 58%, and Fib 32%. Experimental values and predicted values showed significant correlation (IgG: r2 = 0.9962; Fib: r2 = 0.9535; Alb: r2 = 0.9808; TP: r2 = 0.9721, all P < 0.05). Since the solute concentration change in SePE can be predicted, this mass balance formula is useful for setting treatment conditions for both CPE and SePE.

Associations among the plasma amino acid profile, obesity, and glucose metabolism in Japanese adults with normal glucose tolerance.

BACKGROUND: Amino acids (AAs) are emerging as a new class of effective molecules in the etiology of obesity and diabetes mellitus. However, most investigations have focused on subjects with obesity and/or impaired glucose regulation; the possible involvement of AAs in the initial phase of glucose dysregulation remains poorly understood. Furthermore, little attention has been given to possible associations between the pattern/degree of fat deposition and the plasma AA profile. Our objective was therefore to determine the relationships between plasma AA concentrations and the type/degree of obesity and glucose regulation in Japanese adults with normal glucose tolerance. METHODS: Eighty-three subjects with normal glucose tolerance were classified as obese or nonobese and as visceral obesity or nonvisceral obesity. Correlations between the plasma levels of 23 AAs and somatometric measurements, visceral fat area (VFA), subcutaneous fat area (SFA), and 75-g oral glucose tolerance test results were analyzed. RESULTS: Obesity or visceral obesity was associated with higher levels of branched-chain AAs (isoleucine, leucine, and valine), lysine, tryptophan, cystine, and glutamate but lower levels of asparagine, citrulline, glutamine, glycine, and serine (p < 0.04). Age- and gender-adjusted analyses indicated that VFA was positively correlated with tryptophan and glutamate levels, whereas VFA and SFA were negatively correlated with citrulline, glutamine, and glycine levels (p < 0.05). The fasting and 2-h plasma glucose levels or the homeostasis model assessment of insulin resistance were positively correlated with valine, glutamate, and tyrosine levels but negatively correlated with citrulline, glutamine, and glycine levels. The homeostasis model assessment for the ß-cell function index was positively correlated with leucine, tryptophan, valine, and glutamate levels but negatively correlated with citrulline, glutamine, glycine, and serine levels (p < 0.05). CONCLUSIONS: The present study identified specific associations between 10 AAs and the type/degree of obesity, and indices of glucose/insulin regulation, in Japanese adults with preserved glucose metabolism. With the growing concern about the increasing prevalence of obesity and diabetes, the possible roles of these AAs as early markers and/or precursors warrant further investigation.

Right atrial volume and reservoir function are novel independent predictors of clinical worsening in patients with pulmonary hypertension.

BACKGROUND: Symptoms and signs and indices of right heart function are predictors of clinical outcomes in patients with pulmonary hypertension (PH). However, the significance of right atrial (RA) indices has not been sufficiently investigated. We investigated whether RA parameters predict outcomes in patients with pre-capillary PH. METHODS: Study subjects were 68 patients with pre-capillary PH. RA size and function (systolic, reservoir, and conduit functions) were evaluated by cardiac magnetic resonance imaging. RESULTS: During the mean follow-up period of 24 months, 16 of 68 patients experienced clinical worsening (CW), defined as hospitalization because of right heart failure, lung transplantation, or PH-related death. Kaplan-Meier and log-rank test showed that World Health Organization functional class, pericardial effusion, increased brain natriuretic peptide concentration, reduced right ventricular ejection fraction (RVEF), increased minimum RA volume index, and decreased RA reservoir volume were associated with CW-free survival. The combination of RVEF and RA reservoir function was a better predictor of CW-free survival. In univariate Cox hazard proportional analysis, CW was associated with the RA reservoir volume index (hazard ratio [HR] = 0.80). In multivariate analysis, CW was associated with World Health Organization functional class (HR = 4.3), RA minimum volume index (HR = 1.07), and RA reservoir volume index (HR = 0.73). CONCLUSIONS: RA volume and reservoir function and their combined use with RVEF are novel predictors of CW in patients with pre-capillary PH.

Hemodynamic effects of ambrisentan-tadalafil combination therapy on progressive portopulmonary hypertension.

Intravenous epoprostenol is recommended for World Health Organization functional class (WHO-FC) IV patients with pulmonary arterial hypertension (PAH) in the latest guidelines. However, in portopulmonary hypertension (PoPH) patients, advanced liver dysfunction and/or thrombocytopenia often makes the use of intravenous epoprostenol challenging. Here we report the cases of two WHO-FC IV PoPH patients who were successfully treated with a combination of two oral vasodilators used to treat PAH: ambrisentan and tadalafil. Oral vasodilator therapy using a combination of ambrisentan and tadalafil may be a safe and effective therapeutic option for WHO-FC IV PoPH patients and should be considered for selected patients with severe and rapidly progressing PoPH.

Right ventricular (18)F-FDG uptake is an important indicator for cardiac involvement in patients with suspected cardiac sarcoidosis.

PURPOSE: Cardiac sarcoidosis is most commonly found in the left ventricular (LV) free wall. Presence in the right ventricle (RV) is less common but might be useful for detecting cardiac involvement of sarcoidosis. (18)F-fluorodeoxyglucose ((18)F-FDG) PET has been used to detect LV regions with cardiac sarcoidosis. However, the same has not been done for RV involvement. The aims of the current study were to evaluate RV (18)F-FDG uptake and its relationship to the distribution of LV wall (18)F-FDG-positive segments in the LV, and to evaluate whether patients with positive RV (18)F-FDG uptake met the 1993 diagnostic criteria of the Japanese Ministry of Health and Welfare (JMHW) guidelines regarding sarcoidosis with suspected cardiac involvement. METHOD: Fifty-nine biopsy-proven extra-cardiac sarcoidosis patients (age 56.1 ± 14.7 years) with suspected cardiac involvement based on abnormal electrocardiography or echocardiography findings underwent fasting (18)F-FDG PET or PET/CT. The LV wall was divided into 17 segments and RV uptake was also evaluated. RESULT: Among 59 patients, 35 (59.3%) showed some abnormal (18)F-FDG uptake in the RV and/or LV wall. With respect to the RV wall, 13 (22.0%) showed abnormal (18)F-FDG uptake. The number of LV-involved segments was 4.8 ± 2.4 in the patients with RV (18)F-FDG uptake, which was significantly higher than in the patients without RV uptake, 1.8 ± 2.2 (P < 0.0001). Patients with RV uptake more frequently met the diagnostic criteria of the 1993 JMHW guidelines (n = 27), than did those without RV uptake (84.6 vs. 34.8%, P = 0.0033). CONCLUSION: (18)F-FDG PET identified RV involvement less frequently than LV involvement in this study population. However, patients who had RV uptake showed a greater number of LV-involved segments and met the JMHW diagnostic criteria more frequently. Although RV uptake is less frequent, (18)F-FDG RV uptake may be useful in diagnosing cardiac involvement in sarcoidosis. CLINICAL TRIAL REGISTRATION: UMIN000006533.

Right atrial volume and phasic function in pulmonary hypertension.

BACKGROUND: Few studies have focused on right atrial (RA) structure and function in pulmonary hypertension (PH). We sought to evaluate RA volume and phasic function using cardiac magnetic resonance (CMR), and to examine their clinical relevance in PH. METHODS: We prospectively studied 50 PH patients and 21 control subjects. RA volume and indices of phasic function (reservoir volume, ejection fraction [EF], and conduit volume) were evaluated by CMR. RESULTS: Maximum RA volume index was significantly higher in PH patients (56 [44-70] ml/m(2)) than in controls (40 [30-48] ml/m(2)) (p<0.001). Reservoir volume index was significantly lower in PH than in controls (p<0.001), but conduit volume index was higher in PH than in controls (p=0.008). RA EF was similar when comparing the two groups (p=0.925). Interestingly, RA EF was increased in PH patients with WHO functional class III patients as compared with controls (p<0.001) but was reduced in advanced PH patients with WHO functional class IV (p<0.01). Maximum RA volume and RA EF significantly correlated with pulmonary hemodynamic indices, atrial and brain natriuretic hormone levels, and CMR-derived right ventricular indices. By contrast, RA reservoir volume correlated with cardiac index and 6-minute walk distance. CONCLUSIONS: PH is associated with increased size, decreased reservoir function, and increased conduit function of the right atrium. RA systolic function indicated by RA EF increases in patients with mild to moderate PH but decreases in patients with advanced PH. Varying associations between RA indices and conventional PH indices suggest their unique role in the management of PH.

Simple prediction of right ventricular ejection fraction using tricuspid annular plane systolic excursion in pulmonary hypertension.

The present study examined whether tricuspid annular plane systolic excursion (TAPSE) can simply predict right ventricular ejection fraction (RVEF) in patients with pulmonary hypertension (PH). The TAPSE cut-off value to predict reduced RVEF was also evaluated. The association between TAPSE and cardiac magnetic resonance imaging (CMRI)-derived RVEF was examined in 53 PH patients. The accuracy of the prediction equation to calculate RVEF using TAPSE was also evaluated. In PH patients, TAPSE was strongly correlated with CMRI-derived RVEF in PH patients (r = 0.86, p < 0.0001). We then examined the accuracy of the two equations: the original regression equation (RVEF = 2.01 × TAPSE + 0.6) and the simplified prediction equation (RVEF = 2 × TAPSE). Bland-Altman plot showed that the mean difference ± limits of agreement was 0.0 ± 10.6 for the original equation and -0.6 ± 10.6 for the simplified equation. Intraclass correlation coefficient was 0.84 for the original and 0.82 for the simplified equation. Normal RVEF was considered to be ≥40% based on the data from 53 matched controls, and the best TAPSE cut-off value to determine reduced RVEF (<40%) was calculated to be 19.7 mm (sensitivity 88.9%, specificity 84.6%). A simple equation of RVEF = 2 × TAPSE enables easy prediction of RVEF using TAPSE, an easily measurable M-mode index of echocardiography. TAPSE of 19.7 mm predicts reduced RVEF in PH patients with clinically acceptable sensitivity and specificity.

Paradoxical interventricular septal motion as a major determinant of late gadolinium enhancement in ventricular insertion points in pulmonary hypertension.

BACKGROUND: This study investigated the major clinical determinants of late gadolinium enhancement (LGE) at ventricular insertion points (VIPs) commonly seen in patients with pulmonary hypertension (PH). METHODS: Forty-six consecutive PH patients (mean pulmonary artery pressure ≥25 mmHg at rest) and 21 matched controls were examined. Right ventricular (RV) morphology, function and LGE mass volume at VIPs were assessed by cardiac magnetic resonance (CMR). Radial motion of the left ventricular (LV) wall and interventricular septum (IVS) was assessed by speckle-tracking echocardiography. Paradoxical IVS motion index was then calculated. Univariate and multivariate regression analysis were conducted to characterize the relationship between LGE volume at VIPs and PH-related clinical indices, including the paradoxical IVS motion index. RESULTS: Mean pulmonary arterial pressure (MPAP) of PH patients was 38±9 mmHg. LGE at VIPs was observed in 42 of 46 PH patients, and the LGE volume was 2.02 mL (0.47-2.99 mL). Significant correlations with LGE volume at VIPs were observed for MPAP (r = 0.50) and CMR-derived parameters [RV mass index (r = 0.53), RV end-diastolic volume index (r = 0.53), RV ejection fraction (r = -0.56), and paradoxical IVS motion index (r = 0.77)]. In multiple regression analysis, paradoxical IVS motion index alone significantly predicted LGE volume at VIPs (p<0.001). CONCLUSIONS: LGE at VIPs seen in patients with PH appears to reflect altered IVS motion rather than elevated RV pressure or remodeling. Long-term studies would be of benefit to characterize the clinical relevance of LGE at VIPs.

Four cases with group 3 out-of-proportion pulmonary hypertension with a favorable response to vasodilators.

Some patients with group 3 pulmonary hypertension (PH) (PH due to lung disease and/or hypoxia) exhibit disproportionately advanced or "out-of-proportion" PH. In the present case series, we document four consecutive patients with progressive out-of-proportion group 3 PH. All patients exhibited progressive dyspnea or peripheral edema and were treated by pulmonary artery hypertension (PAH)-specific vasodilator(s). At the follow-up assessment 3-4 months later, symptoms/signs and pulmonary hemodynamic measurements improved in all four patients (45 ± 8% decrease in pulmonary vascular resistance). Pulmonary oxygenation deteriorated in one patient but improved or did not significantly change in the remaining three cases. Importantly, the background lung parenchymal disease (early-onset chronic obstructive pulmonary disease, rheumatoid arthritis-associated interstitial pneumonia, and combined pulmonary fibrosis and emphysema) was stable upon progression of the right heart failure symptoms/signs, and also during the 3-4-month follow-up period in all cases. We herein describe the clinical features of the four cases and discuss the potential benefits and risks of PAH-specific treatment in this emerging population.

Validation study on the accuracy of echocardiographic measurements of right ventricular systolic function in pulmonary hypertension.

BACKGROUND: The accuracy of echocardiographic parameters of right ventricular (RV) function has not been sufficiently validated in patients with pulmonary hypertension (PH). The aim of this study was to evaluate whether echocardiographic measurements reliably reflect RV systolic function in PH using cardiac magnetic resonance imaging (CMRI)-derived RV ejection fraction (RVEF) as a gold standard. METHODS: A total of 37 consecutive patients with PH, 20 with pulmonary arterial hypertension, 12 with chronic thromboembolic PH, and five others, were prospectively studied. All patients underwent echocardiography, CMRI, and right-heart catheterization within a 1-week interval. Associations between five echocardiography-derived parameters of RV systolic function and CMRI-derived RVEF were evaluated. RESULTS: All five echocardiography-derived parameters were significantly correlated with CMRI-derived RVEF (percentage RV fractional shortening: r = 0.48, P = .0011; percentage RV area change: r = 0.40, P = .0083; tricuspid annular plane systolic excursion [TAPSE]: r = 0.86, P < .0001; RV myocardial performance index: r = -0.59, P < .0001; and systolic lateral tricuspid annular motion velocity: r = 0.63, P < .0001). Compared with the other indices, TAPSE exhibited the highest correlation coefficient. Of the five echocardiographic measurements, only TAPSE significantly predicted CMRI-derived RVEF in multiple regression analysis (P < .0001). Intraobserver and interobserver reproducibility was favorable for all five indices and was particularly high for TAPSE and systolic lateral tricuspid annular motion velocity. CONCLUSIONS: Echocardiographic measurements are promising noninvasive indices of RV systolic function in patients with PH. In particular, TAPSE is superior to other indices in accuracy.