Neurodevelopmental Outcomes of High-Risk Preterm Infants: A Prospective Study in Japan.

OBJECTIVES: To determine the neurodevelopmental outcomes of very-low-birth-weight infants (VLBWIs, birth weight <1,500 g) after 9 years of follow-up. METHODS: This study prospectively recruited 224 VLBWIs born from 2003 to 2009 in Kyushu University Hospital, Japan. Comorbidities of neurocognitive impairment, epilepsy, and autism spectrum disorder or attention-deficit hyperactivity disorder (ASD/ADHD) were assessed at age 3, 6, and 9 years. RESULTS: Neurodevelopmental profiles were obtained from 185 (83%), 150 (67%), and 119 (53%) participants at age 3, 6, and 9 years, respectively. At age 9 years, 25 (21%) VLBWIs showed intelligence quotient (IQ) <70, 11 (9%) developed epilepsy, and 14 (12%) had a diagnosis of ASD/ADHD. The prevalence of epilepsy was higher in children with an IQ <70 at age 9 years than in those with an IQ ≥70 (44% vs 0%). In contrast, ASD/ADHD appeared at similar frequencies in children with an IQ <70 (16%) and ≥70 (11%). Perinatal complications and severe brain lesions on MRI were considered common perinatal risks for developmental delay and epilepsy but not for ASD/ADHD. Male sex was identified as a unique risk factor for ASD/ADHD. CONCLUSION: These data suggest that VLBWIs showed a higher prevalence of developmental delay, epilepsy, and ASD/ADHD at age 9 years than the general population. Distinct mechanisms might be involved in the pathogenic process of ASD/ADHD from those of developmental delay and epilepsy.

Clinical Subtypes in Children with Attention-Deficit Hyperactivity Disorder According to Their Child Behavior Checklist Profile.

This study sought to identify subgroups of attention-deficit hyperactivity disorder (ADHD) defined by specific patterns of emotional and behavioral symptoms according to the parent-rated Child Behavior Checklist (CBCL). Our clinical sample comprised 314 children (aged 4 to 15 years) diagnosed with ADHD according to the DSM-5. In addition, comorbid psychiatric disorders, general functioning, and medication status were assessed. Cluster analysis was performed on the CBCL syndrome subscales and yielded a solution with four distinct subgroups. The "High internalizing/externalizing" group displayed an overlap between internalizing and externalizing problems in the CBCL profile. In addition, the "High internalizing/externalizing" group revealed a high rate of comorbid autism spectrum disorder and elevated autistic traits. The "Inattention and internalizing" group revealed a high rate of the predominantly inattentive presentation according to ADHD specifier from the DSM-5. The "Aggression and externalizing" group revealed a high rate of comorbid oppositional defiant disorder and conduct disorder. The "Less psychopathology" group scored low on all syndrome scales. Children with ADHD were subdivided into four distinct subgroups characterized by psychopathological patterns, with and without internalizing and externalizing problems. The overlap between internalizing and externalizing problems may be mediated with emotional dysregulation and associated neurobiological bases.

Dual Functions of TEMPO-Oxidized Cellulose Nanofibers in Oil-in-Water Emulsions: A Pickering Emulsifier and a Unique Dispersion Stabilizer.

The emulsifying and dispersing mechanisms of oil-in-water emulsions stabilized by 2,2,6,6-tetramethylpiperidin-1-oxyl (TEMPO)-oxidized cellulose nanofibers (CNFs) have been investigated. The emulsifying mechanism was studied by changing the oil/water interfacial tension from 8.5 to 53.3 mN/m using various types of oils. The results showed that the higher the oil/water interfacial tension, the greater is the amount of CNFs adsorbed at the oil/water interface, making the CNF-adsorbed oil-in-water emulsions thermodynamically more stable. Moreover, the amount of CNFs adsorbed on the surfaces of the oil droplets increased with increasing interfacial area. The dispersion stability of the oil droplets was dominated by the CNF concentration in the water phase. Above the critical concentration (0.15% w/w), the CNFs formed network structures in the water phase, and the emulsion was effectively stabilized against creaming. Emulsion formation and the CNF network structures in the emulsion were visualized by cryo-scanning electron microscopy.

Atrial electrical abnormality in patients with Brugada syndrome assessed by signal-averaged electrocardiography.

BACKGROUND: Ventricular fibrillation and atrial fibrillation are well-known arrhythmias in patients with Brugada syndrome. This study evaluated the characteristics of the atrial arrhythmogenic substrate using the signal-averaged electrogram (SAECG) in patients with Brugada syndrome. METHODS: SAECGs were performed during normal sinus rhythm in 23 normal volunteers (control group), 21 patients with paroxysmal atrial fibrillation (PAF; PAF group), and 21 with Brugada syndrome (Brugada group). RESULTS: The filtered P wave duration (fPd) in the control, Brugada, and PAF groups was 113.9±12.9ms, 125.3±15.0ms, and 137.1±16.3ms, respectively. The fPd in the PAF group was significantly longer compared to that in the control and Brugada groups (p<0.05). The fPd in the Brugada group was significantly longer than that in the control group (p<0.05) and significantly shorter than that in the PAF group (p<0.05). CONCLUSION: Patients with Brugada syndrome had abnormal P waves on the SAECG. The abnormal P waves on the SAECG in Brugada syndrome patients may have intermediate characteristics between control and PAF patients.

Partial left superior pulmonary vein potential elimination by an inferior ganglionated plexus ablation.

Ganglionated plexus (GP) plays an important role in the initiation and maintenance of atrial fibrillation (AF). The GP ablation has been found to be effective for AF treatment. In this case, we reported an AF case in which the pulmonary vein (PV) potentials of the anterior region of the left superior PV were eliminated by an inferior right GP ablation.

A Comparison between the Instantaneous Wave-free Ratio and Resting Distal Coronary Artery Pressure/Aortic Pressure and the Fractional Flow Reserve: The Diagnostic Accuracy Can Be Improved by the Use of both Indices.

Objectives The fractional flow reserve (FFR) is an index of the severity of coronary stenosis that has been clinically validated in several studies. The instantaneous wave-free ratio (iFR) and the resting distal coronary artery pressure/aortic pressure (Pd/Pa) are nonhyperemic pressure-derived indices of the severity of stenosis. This study sought to examine the diagnostic accuracy of the iFR and resting Pd/Pa with respect to hyperemic FFR. Methods Following an intracoronary injection of papaverine, the iFR, resting Pd/Pa, and FFR were continuously measured in 123 lesions in 103 patients with stable coronary disease. Results The iFR and resting Pd/Pa values were strongly correlated with the FFR (R=0.794, p<0.001, R=0.832, p<0.0001, respectively). A receiver operator curve (ROC) analysis revealed that the optimal iFR cut-off value for predicting an FFR of <0.80 was 0.89 (AUC 0.901, sensitivity 84.1%, specificity 80.0%, positive predictive value 69.8%, negative predictive value 90.0%, diagnostic accuracy 81.3%), while the optimal resting Pd/Pa cut-off value was 0.92 (AUC 0.925, sensitivity 90.9%, specificity 78.5%, positive predictive value 70.2%, negative predictive value 93.9%, diagnostic accuracy 82.9%). The lesions with an iFR value of ≤0.89 and a Pd/Pa value of ≤0.92 were defined as double-positive lesions, while the lesions with an iFR value of >0.89 and a Pd/Pa value of >0.92 were defined as double-negative lesions. In these 109 lesions, the sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were 92.3%, 82.9%, 75.0%, 95.1%, and 86.2%, respectively. Conclusion This analysis demonstrated that the iFR and resting Pd/Pa were strongly correlated with the FFR and that the diagnostic accuracy of the iFR was similar to that of the resting Pd/Pa. The diagnostic accuracy can be improved with the use of both the iFR and the resting Pd/Pa.

Contrast-induced Hyperemia as an Alternative to Drug-induced Hyperemia in the Evaluation of the Fractional Flow Reserve in Coronary Lesions.

Objective Measuring the fractional flow reserve (FFR) requires the induction of coronary hyperemia, usually with adenosine, adenosine triphosphate (ATP), or papaverine. However, adenosine can induce rhythmic complications, and intracoronary boluses of papaverine that prolong the QT interval can cause ventricular tachycardia. Injection of contrast media, which is routinely performed to validate the FFR guidewire placement, also induces hyperemia and may be an alternative method of measuring the FFR. We evaluated the diagnostic accuracy of the FFR after contrast hyperemia (FFRcont) compared to FFR evaluated after intracoronary papaverine (FFRpp). Methods This study included 109 lesions in 93 patients (mean age 70.4±8.7 years) with stable coronary disease. The FFR was measured as follows: 1) baseline pressure value; 2) FFRcont after intracoronary contrast injection (iopamidol, 8 mL for left coronary artery [LCA] or 6 mL for right coronary artery [RCA]); 3) FFRpp after intracoronary injection of papaverine (12 mg for LCA or 8 mg for RCA). Results FFRcont values were strongly correlated with FFRpp (R=0.940, p<0.0001; FFRpp = FFRcont ×1.007-0.032). The best cut-off point in the receiver operator curve analysis for predicting a FFRpp <0.80 was 0.82 (area under the curve =0.980; sensitivity 95.1%, specificity 91.2%, positive predictive value 86.7%, negative predictive value 96.9%). Conclusion FFRcont is highly accurate for predicting FFRpp. An FFRcont threshold value of 0.82 provides excellent sensitivity and a negative predictive value. FFRcont is an alternative method of inducing hyperemia.

The Difference between the optical coherence tomography (OCT) findings of newly progressed coronary lesions in symptomatic and asymptomatic patients.

BACKGROUND: Generally, newly progressed coronary lesions (NPCLs) are considered to be composed of lipid-rich plaques. In case of vulnerable plaque rupture, they may quickly become culprit lesions responsible for acute coronary syndromes. METHODS: Between September 2011 and September 2015, 2034 patients underwent scheduled follow-up coronary angiography (CAG) after percutaneous coronary intervention (PCI) in Tsuchiya General Hospital. Patients with NPCLs found by CAG during the follow-up period were evaluated by optical coherence tomography (OCT). NPCLs were defined as the lesions with less than 50% diameter stenosis, which progressed to more than 75% diameter stenosis within 3years after the previous CAG. Patients with restenosis after PCI were excluded. We compared OCT findings of NPCLs between symptomatic and asymptomatic patients. RESULTS: The follow-up CAG showed NPCLs in 64 patients (3.2%). OCT revealed fibrous plaque in 42 patients (65.6%) and thin-cap fibroatheroma in one patient. Thirteen patients had chest symptoms for one month before CAG and the remaining 51 patients were asymptomatic. The prevalence of fibrous plaque and intimal disruption or plaque rupture were not significantly different between symptomatic and asymptomatic patients (61.5% vs. 66.7%, p=0.752 and 30.8% vs. 11.8%, p=0.213, respectively). However, thrombi were more frequently observed in symptomatic patients (61.5% vs. 13.7%, p<0.001). CONCLUSIONS: The majority of NPCLs found in asymptomatic patients at follow-up CAG were not vulnerable; however, those found in symptomatic patients might be vulnerable. In clinical practice, NPCLs found in asymptomatic patients should be evaluated for functional severity of stenosis in order to determine the need for coronary revascularization.

Effect of epicuticular wax crystals on the localization of artificially deposited sub-micron carbon-based aerosols on needles of Cryptomeria japonica.

Elucidation of the mechanism of adsorption of particles suspended in the gas-phase (aerosol) to the outer surfaces of leaves provides useful information for understanding the mechanisms of the effect of aerosol particles on the growth and physiological functions of trees. In the present study, we examined the localization of artificially deposited sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica, a typical Japanese coniferous tree species, by field-emission scanning electron microscopy. The clusters (aggregates) of carbon-based particles were deposited on the needle surface regions where epicuticular wax crystals were sparsely distributed. By contrast, no clusters of the particles were found on the needle surface regions with dense distribution of epicuticular wax crystals. Number of clusters of carbon-based particles per unit area showed statistically significant differences between regions with sparse epicuticular wax crystals and those with dense epicuticular wax crystals. These results suggest that epicuticular wax crystals affect distribution of carbon-based particles on needles. Therefore, densely distributed epicuticular wax crystals might prevent the deposition of sub-micron-sized carbon-based particles on the surfaces of needles of Cryptomeria japonica to retain the function of stomata.

Cavitation of intercellular spaces is critical to establishment of hydraulic properties of compression wood of Chamaecyparis obtusa seedlings.

BACKGROUND AND AIMS: When the orientation of the stems of conifers departs from the vertical as a result of environmental influences, conifers form compression wood that results in restoration of verticality. It is well known that intercellular spaces are formed between tracheids in compression wood, but the function of these spaces remains to be clarified. In the present study, we evaluated the impact of these spaces in artificially induced compression wood in Chamaecyparis obtusa seedlings. METHODS: We monitored the presence or absence of liquid in the intercellular spaces of differentiating xylem by cryo-scanning electron microscopy. In addition, we analysed the relationship between intercellular spaces and the hydraulic properties of the compression wood. KEY RESULTS: Initially, we detected small intercellular spaces with liquid in regions in which the profiles of tracheids were not rounded in transverse surfaces, indicating that the intercellular spaces had originally contained no gases. In the regions where tracheids had formed secondary walls, we found that some intercellular spaces had lost their liquid. Cavitation of intercellular spaces would affect hydraulic conductivity as a consequence of the induction of cavitation in neighbouring tracheids. CONCLUSIONS: Our observations suggest that cavitation of intercellular spaces is the critical event that affects not only the functions of intercellular spaces but also the hydraulic properties of compression wood.

Comparison of everolimus- and paclitaxel-eluting stents in dialysis patients.

BACKGROUND: We previously reported that the incidence of 1-year major adverse cardiac events (MACE) in patients treated with paclitaxel-eluting stents (PES) was lower than that in the sirolimus-eluting stents in dialysis patients. However, it remains unclear whether there are differences in clinical outcomes between everolimus-eluting stents (EES) and PES. METHODS: Between February 2010 and September 2013, 102 maintenance dialysis patients with 135 lesions treated with EES were compared to 107 maintenance dialysis patients with 147 lesions treated with PES. One-year clinical outcomes were investigated. RESULTS: Diabetes mellitus was present in 64.7% in the EES group and 71.0% in the PES group (p = 0.33). Heavy calcification was in 27.4% vs. 34.0% (p = 0.23). Rotational atherectomy was undergone in 11.1% vs. 23.1% (p < 0.01). Total stented length was not significantly different (23.5 ± 14.6 mm vs. 24.4 ± 13.2 mm, p = 0.60). One patient in the EES group was lost to follow up. At 12 months, MACE occurred in 13.2% in the EES group and 17.4% in the PES group (p = 0.25). Target lesion revascularization (TLR) was observed in 9.5% vs. 10.4% respectively (p = 0.77). Mortality was 11.8% vs. 13.1% (p = 0.35). Cardiac death was 5.0% vs. 7.7% (p = 0.09). Definite stent thrombosis was observed in 2.0% vs. 0% (p = 0.14). Subgroup analysis in patients with diabetes mellitus revealed no significant differences in MACE (12.7% vs. 14.9%, p = 0.36), TLR (8.3% vs. 7.4%, p = 0.42), mortality (13.7% vs. 13.2%, p = 0.28), and cardiac death (6.3% vs. 8.0%, p = 0.15) between the two groups. CONCLUSIONS: One-year clinical outcomes following EES and PES implantations are similar in dialysis patients.

Validation of lactate level as a predictor of early mortality in acute decompensated heart failure patients who entered intensive care unit.

BACKGROUND: The significance of routine measurement of lactate level is unclear in patients with critical acute decompensated heart failure (ADHF). METHODS AND RESULTS: Consecutive 754 patients who were admitted to the intensive care unit (ICU) in our hospital from January 2007 to March 2012 and given a diagnosis of ADHF were eligible for retrospective entry into the registry. Lactate level was measured on admission from routine arterial blood sample and we investigated by comparing the lactate level and parameters of conventional in-hospital mortality predictors. Among the patients, 88 (12%) died during hospitalization. The lactate level had great power to predict in-hospital mortality, as suggested by the c-statistics of 0.71. The occurrence of in-hospital death was more pronounced in patients with high levels of lactate (>3.2mmol/l) and the tendency was observed in patients in both the acute coronary syndrome (ACS) group and non-ACS group. In multivariate analysis, elevated lactate levels remained an independent predictor of in-hospital death (odds ratio, 2.14; 95% confidence interval, 1.10-4.21; p=0.03). CONCLUSIONS: Elevated levels of arterial lactate on admission were related to worse in-hospital mortality in patients with ADHF either with or without ACS, suggesting that the presence of high lactate in patients who enter the ICU with ADHF could help stratify the initial risk of early mortality.

Comparison of sirolimus- and paclitaxel-eluting stents in patients with moderate renal insufficiency: results from the J-DESsERT trial.

BACKGROUND: It is unclear whether there are differences in clinical outcomes between sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) in patients with moderate renal insufficiency (RI). METHODS: The Japan-Drug Eluting Stents Evaluation; a Randomized Trial (J-DESsERT) was a prospective, randomized multicenter trial which compared 1:1 coronary stenting between SES and PES patients. Patient with serious RI (serum creatinine value 2mg/dL or higher) were excluded. Patients were classified into 2 arms according to renal function: a non-RI arm of 2220 patients (SES 1094 and PES 1126 patients with estimated glomerular filtration rate (eGFR) ≥60 mL min(-1) 1.73 m(-2)) and an RI arm of 1206 patients (SES 613, PES 593 with 30≤eGFR <60 mL min(-1) 1.73 m(-2)). RESULTS: At 12 months, the primary endpoint of target vessel failure in the non-RI arm occurred in 6.0% in the SES group and 8.7% in the PES group (p=0.02). In the RI arm, this occurred in 5.7% and 8.1% (p=0.10). Mortality rates were 0.8% vs 0.7% (p=0.78) in the non-RI arm, and 2.2% vs 2.1% (p=0.90) in the RI arm. Cardiac death was 0.4% vs 0.1% (p=0.17) in the non-RI arm, and 1.0% vs 1.0% (p=0.96) in the RI arm. Mortality was higher in patients with RI than those without RI (2.1% vs 0.8%; p<0.01). Cardiac death rates increased in the RI arm compared with those in the non-RI arm (1.0% vs 0.2%; p<0.01). CONCLUSIONS: Regardless of the presence or absence of moderate RI, differences in outcomes between SES and PES change little except mortality and cardiac death.

Causes of very late stent thrombosis investigated using optical coherence tomography.

OBJECTIVE: Very late stent thrombosis (VLST) remains an unresolved problem, and recent reports have indicated that VLST onset can occur in patients treated with both drug-eluting stents (DES) and bare metal stents (BMS). We evaluated the causes of VLST using optical coherence tomography (OCT). METHODS: OCT was performed in 22 patients (12 DES-treated patients, 10 BMS-treated patients). Because two instances of VLST occurred simultaneously in one case in the DES group, the DES group comprised 13 lesions, while the BMS group comprised 10 lesions. All struts were counted in each frame, and the proportion of uncovered or malapposed struts was calculated based on the overall number of struts in the stent. RESULTS: The interval from stent implantation to VLST onset was significantly longer in the BMS group. The proportion of uncovered struts and the ratio of malapposed struts were significantly higher in the DES group than in the BMS group. The OCT analysis demonstrated intimal hyperplasia or intimal disruption in all patients in the BMS group. However, in the DES group, severe hyperplasia and/or neoatherosclerosis was observed in only eight lesions (61.5%), while uncovered and malapposed struts were involved in the other lesions. CONCLUSION: In most BMS-treated lesions, it appeared that VLST was caused by the occurrence of neoatherosclerosis after stent implantation. The causes of VLST in DES-treated lesions are more various and complicated than those observed for BMS-treated lesions.

Effect of statin on the 5 years clinical outcomes in dialysis patients treated with sirolimus-eluting stent.

OBJECTIVE: The optimal medication therapies are recommended in patients with coronary artery disease even after the coronary revascularization. However, the information of optimal medical therapy in dialysis population is scant. We assessed the efficacy of statin on the clinical outcomes after Sirolimus-eluting stent (SES) implantation in patients with and without dialysis. METHODS AND RESULTS: We analyzed date from 843 consecutive patients who successfully treated with SES in our institution between August 2004 and November 2006. Among patients, 96 patients (11.4%) were undergoing dialysis. In non-dialysis patients, 405 patients (54%) were treated with statin at hospital discharge. In dialysis patients, only 16 patients (17%) were treated with statin. In non-dialysis patients, mortality rate was significantly lower in patients treated with statin than those without statin (4.4% vs. 13.9%, p<0.0001). While in dialysis patients, mortality rate was similar between patients treated with and without statin (56.3% vs. 57.6%, p=0.86). After adjusting for confounders, the hazard ratios for mortality were 0.39 (95% confidence interval (CI), 0.14-0.99; p=0.047) in non-dialysis patients and 1.79 (95% CI, 0.39-7.86; 0.45) for dialysis patients. The interaction probability between statin use and dialysis for mortality was 0.016. CONCLUSION: The use of statin may have beneficial effect on reducing mortality rate in patients after SES implantation in non-dialysis patients. However, such favorable effect was not observed in dialysis population.

Spontaneous disappearance of coronary pseudoaneurysm due to coronary artery perforation following percutaneous coronary intervention.

In recent years, while therapeutic outcome after percutaneous coronary intervention is improving due to the introduction of drug-eluting stent and device development, procedure-related complications including coronary perforation may ineluctably occur though at low-frequency, even if careful manipulations are performed under IVUS guidance. Meanwhile, coronary pseudoaneurysm subsequent to coronary perforation is one of the complications at chronic phase infrequently experienced following percutaneous coronary intervention. To date, the incidence and natural history of pseudoaneurysm following coronary artery perforation remain unclear. We experienced a case with coronary pseudoaneurysm developed 2 weeks after Ellis II-type coronary artery perforation which spontaneously disappeared 4 months later. As the mechanism of disappearance, thrombotic occlusion was confirmed upon intravascular ultrasound.

Comparison of heart-type fatty acid binding protein and sensitive troponin for the diagnosis of early acute myocardial infarction.

BACKGROUND: The current development of serological biomarkers allows detection of smaller myocardial necrosis and early acute myocardial infarction (AMI). We evaluated the relevance of the heart-type fatty acid binding protein (H-FABP) assay, which has recently been approved in Japan, for early diagnosis of AMI as compared with the sensitive troponin assay. METHODS: This is an observational study in a single center. From 2010 July to 2011 January, 114 patients who presented with symptoms suggestive of AMI were enrolled. RESULTS: AMI was adjudicated in 45 patients (40%). The diagnostic accuracy of measurements obtained at presentation for AMI, as quantified by the area under the receiver-operating-characteristic curve (AUC), was significantly lower with H-FABP assay than the sensitive troponin assay [AUC for H-FABP, 0.59; 95% confidence interval (CI) 0.48-0.70; and for troponin I, 0.89; 95% CI, 0.83-0.94; P<.0001]. Among patients who presented within 2h after the onset of chest pain, the AUC for H-FABP was even low as compared with sensitive troponin (0.55; 0.39-0.72 vs. 0.89; 0.80-0.98, p<0.001). The clinical sensitivity for the diagnosis of AMI with the cutoff point of 99 th percentile was similar in both assays (81% and 81%, respectively), however, the specificity was extremely low in the H-FABP assay as compared with sensitive troponin assay (19% and 79%, respectively). CONCLUSION: The measurement of H-FABP in 114 consecutive patients with chest pain suggestive of AMI showed no improvement of diagnosis for early AMI as compared with the current sensitive troponin assay because of its extremely low specificity.

Impact of culprit plaque volume and composition on myocardial microcirculation following primary angioplasty in patients with ST-segment elevation myocardial infarction: virtual histology intravascular ultrasound analysis.

BACKGROUND: An impaired myocardial perfusion state after primary angioplasty is a strong predictor of long-term adverse outcomes in patients with STEMI. We assessed the relationship between culprit plaque characteristics and myocardial perfusion state after primary angioplasty in patients with ST-segment elevation myocardial infarction (STEMI). METHODS: A total of 101 consecutive patients with de novo STEMI were divided into 3 groups according to the state of myocardial perfusion assessed by ST-segment elevation resolution (STR): Group A (complete: STR ≥ 70%, n=26), Group B (partial: STR<70% but ≥ 30%, n=55) and Group C (none: STR<30%, n=20). We analyzed plaque features by virtual histology intravascular ultrasound (VH-IVUS) and assessed the relationship between culprit plaque characteristics and STR after primary angioplasty. RESULTS: Total plaque volume was significantly higher in Group C than in Groups A and B (146.4 ± 38.0 mm(3)vs. 93.3 ± 29.1 mm(3) and 105.8 ± 31.5 mm(3), p<0.001, respectively). Necrotic core (NC) volume was also significantly higher in Group C than in Groups A and B (25.4 ± 8.0m m(3), vs. 11.9 ± 6.3 mm(3) and 17.3 ± 9.7 mm(3), p<0.001, respectively). Analysis of receiver-operating characteristic curves revealed that total plaque volume and NC volume had the best diagnostic accuracy of all the VH-IVUS parameters to predict STR<30%. The optimal cutoff values (sensitivity/specificity) were 123.4 mm(3) (75.0%/75.3%) for total plaque volume and 20.3mm(3) (75.0%/74.1%) for NC volume. CONCLUSIONS: Culprit plaque with large plaque burden and high NC volume is closely associated with poor STR after revascularization.

A rapid decrease in temperature induces latewood formation in artificially reactivated cambium of conifer stems.

BACKGROUND AND AIMS: Latewood formation in conifers occurs during the later part of the growing season, when the cell division activity of the cambium declines. Changes in temperature might be important for wood formation in trees. Therefore, the effects of a rapid decrease in temperature on cellular morphology of tracheids were investigated in localized heating-induced cambial reactivation in Cryptomeria japonica trees and in Abies firma seedlings. METHODS: Electric heating tape and heating ribbon were wrapped on the stems of C. japonica trees and A. firma seedlings. Heating was discontinued when 11 or 12 and eight or nine radial files of differentiating and differentiated tracheids had been produced in C. japonica and A. firma stems, respectively. Tracheid diameter, cell wall thickness, percentage of cell wall area and percentage of lumen area were determined by image analysis of transverse sections and scanning electron microscopy. KEY RESULTS: Localized heating induced earlier cambial reactivation and xylem differentiation in stems of C. japonica and A. firma as compared with non-heated stems. One week after cessation of heating, there were no obvious changes in the dimensions of the differentiating tracheids in the samples from adult C. japonica. In contrast, tracheids with a smaller diameter were observed in A. firma seedlings after 1 week of cessation of heating. Two or three weeks after cessation of heating, tracheids with reduced diameters and thickened cell walls were found. The results showed that the rapid decrease in temperature produced slender tracheids with obvious thickening of cell walls that resembled latewood cells. CONCLUSIONS: The results suggest that a localized decrease in temperature of stems induces changes in the diameter and cell wall thickness of differentiating tracheids, indicating that cambium and its derivatives can respond directly to changes in temperature.