Visualization of collateral channels with coronary computed tomography angiography for the retrograde approach in percutaneous coronary intervention for chronic total occlusion.

BACKGROUND: There have been no reports about the diagnostic ability of coronary computed tomography angiography (CTA) in evaluating collateral channels used for retrograde chronic total occlusion (CTO) percutaneous coronary intervention (PCI). OBJECTIVE: We investigated the ability and diagnostic accuracy of coronary CTA compared with invasive coronary angiography to detect collaterals used in retrograde CTO PCI and to compared the success rates for wire crossing between collaterals that are detectable and not detectable in coronary CTA. METHODS: We retrospectively reviewed data from 43 patients (55 collaterals) who underwent coronary CTA and PCI for CTO with the retrograde approach. We compared the ability of coronary CTA to visualize collaterals to invasive coronary angiography and evaluated the rates of successful wire crossing between CTA-visible and invisible collaterals. RESULTS: The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of coronary CTA for detecting collaterals which were used for the retrograde approach was 100.0%, 50.0%, 65.9%, 100.0%, and 74.5%, respectively. Guidewire collateral crossing was more successful in CT-visible collaterals than those not detectable in CT (74.1% vs. 46.4%, p = 0.034). There were fewer collateral vessel injuries in CTA-visible collaterals (11.1% vs. 32.1%, p = 0.041). CONCLUSION: Coronary CTA provides good visualization of collaterals used in retrograde CTO PCI. For retrograde guidewire crossing, a higher success rate with fewer complications was observed in CTA-visible collaterals than in those not detectable in coronary CTA.

Effect of confinement on the fluid properties of ammonia in mesopores of MCM-41 and SBA-15.

The effect of pore size on capillary condensation and solid-liquid phase changes of ammonia in MCM-41 and SBA-15 was studied by adsorption and FTIR measurements of condensed phases at low temperatures. Adsorption isotherms are all typical type IV on the fully hydroxylated surfaces, without hysteresis loops in the smaller pores (d < 2.4 nm). In the larger pores, hysteresis loops appear at lower temperatures and disappear with increasing temperature, i.e., the capillary critical phenomenon was detected (hysteresis critical point). The criticality of the adsorption hysteresis loop is very similar to that for nonpolar nitrogen in mesopores of various shapes, suggesting that this is a universal phenomenon among fluids in mesopores. Freezing and melting of capillary-condensed ammonia were observed by FTIR spectroscopy. The melting temperature of capillary-condensed ammonia decreased with decreasing pore size, which is similar in the behavior of freezing. In the smaller pores (d < 2.4 nm); however, ammonia was not frozen. It is suggested that the capillary-condensed inner part, i.e., inside the ammonia monolayer, is affected too much by the pore wall and/or is too small in volume to crystallize. In the larger pores of SBA-15, crystallization is remarkably segregated from ammonia molecules strongly coordinated to surface hydroxyls.

Myocardial imaging with 18F-fluoro-2-deoxyglucose positron emission tomography and magnetic resonance imaging in sarcoidosis.

PURPOSE: Despite accumulating reports on the clinical value of (18)F-fluoro-2-deoxyglucose positron emission tomography (18F-FDG PET) and magnetic resonance imaging (MRI) in the assessment of cardiac sarcoidosis, no studies have systematically compared the images of these modalities. METHODS: Twenty-one consecutive patients with suspected cardiac sarcoidosis underwent cardiac examinations that included 18F-FDG PET and MRI. The association of 18F-FDG PET and MRI findings with blood sampling data such as serum angiotensin converting enzyme levels was also evaluated. RESULTS: Eight of 21 patients were diagnosed as having cardiac sarcoidosis according to the Japanese Ministry of Health and Welfare Guidelines for Diagnosing Cardiac Sarcoidosis. Sensitivity and specificity for diagnosing cardiac sarcoidosis were 87.5 and 38.5%, respectively, for 18F-FDG PET, and 75 and 76.9%, respectively, for MRI. When the 18F-FDG PET and MRI images were compared, 16 of 21 patients showed positive findings in one (n = 8) or both (n = 8) of the two modalities. In eight patients with positive findings on both images, the distribution of the findings differed among all eight cases. The presence of positive findings on 18F-FDG PET was associated with elevated serum angiotensin-converting enzyme levels; this association was not demonstrated on MRI. CONCLUSIONS: Both 18F-FDG PET and MRI provided high sensitivity for diagnosing cardiac sarcoidosis in patients with suspected cardiac involvement, but the specificity of (18)F-FDG PET was not as high as previously reported. The different distributions of the findings in the two modalities suggest the potential of 18F-FDG PET and MRI in detecting different pathological processes in the heart.

Pilot study of short-term effects of a novel long-acting oral beraprost in patients with pulmonary arterial hypertension.

BACKGROUND: Oral prostacyclin analogs can improve the prognosis of patients with mild to moderate pulmonary arterial hypertension (PAH), but because they often provoke adverse effects, such as flushing and dizziness, administering the optimal dose can be difficult. METHODS AND RESULTS: In the present study, a novel long-acting oral beraprost (TRK-100STP: 0-360 mug/day for 12 weeks) was administered to 4 patients with mild to moderate PAH. The patients tolerated the drug well with mild adverse manifestations and negligible effects on the systemic circulation. In contrast, pulmonary vascular resistance decreased by 27+/-12% and the 6-min walk test distance increased by 11+/-11%. CONCLUSIONS: TRK-100STP is a novel option in the medical management of patients with PAH.

Phase separation of acetonitrile-water mixtures and minimizing of ice crystallites from there in confinement of MCM-41.

The effect of confinement of an acetonitrile-water mixture, whose correlation length was comparable to the pore size of the mesopores of MCM-41 (d=2.4-3.6 nm), on the phase changes was studied. Used techniques were low temperature differential scanning calorimetry and Fourier transform infrared spectroscopy, where the phase separation, lowering of the freezing and melting temperatures, and phase transitions of the acetonitrile were detected. The latter occurred in the mesopores at temperatures similar to that of the pure liquid, while the melting temperature of the water in the mesopores<3.1 nm decreased markedly at higher acetonitrile contents, suggesting a marked lowering of ice crystallite size.

Estimation of beta-cell function from the data of the oral glucose tolerance test.

Although a hyperbolic relationship between insulin secretion and insulin sensitivity has been shown, the relationship has been often questioned. We examined the relationship using oral glucose tolerance test (OGTT)-derived indexes. A total of 374 Japanese subjects who had never been given a diagnosis of diabetes underwent a 75-g OGTT. In subjects with normal glucose tolerance (NGT), the ln [insulinogenic index (IGI)] was described by a linear function of ln (x) (x, insulin sensitivity index) in regression analysis when the reciprocal of the insulin resistance index in homeostasis model assessment, Matsuda's index, and oral glucose insulin sensitivity index were used as x. Because the 95% confidence interval of the slope of the regression line did not necessarily include -1, the relationships between IGI and x were not always hyperbolic, but power functions IGI x x(alpha) = a constant. We thought that IGI x x(alpha) was an appropriate beta-cell function estimate adjusted by insulin sensitivity and referred to it as beta-cell function index (BI). When Matsuda's index was employed as x, the BI values were decreased in subjects without NGT. Log BI had a better correlation with fasting plasma glucose (PG; FPG) and 2-h PG in non-NGT subjects than in NGT subjects. In subjects with any glucose tolerance, log BI was linearly correlated with 1-h PG and glucose spike (the difference between maximum PG and FPG). In conclusion, the relationship between insulin secretion and insulin sensitivity was not always hyperbolic. The BI is a useful tool in the estimation of beta-cell function with a mathematical basis.

Enthalpy and interfacial free energy changes of water capillary condensed in mesoporous silica, MCM-41 and SBA-15.

The effect of confinement on the solid-liquid phase transitions of water was studied by using DSC and FT-IR measurements. Enthalpy changes upon melting of frozen water in MCM-41 and SBA-15 were determined as a function of pore size and found to decrease with decreasing pore size. The melting point also decreased almost monotonically with a decrease in pore size. Analysis of the Gibbs-Thomson relation on the basis of the thermodynamic data showed that there were two stages of interfacial free energy change after the constant region, i.e., below a pore size of 6.0 nm: a gradual decrease down to 3.4 nm and another decrease after a small jump upward. This fact demonstrates that the simple Gibbs-Thomson relation, i.e., a linear relation between the melting point change and the inverse pore size, is limited to the range not far from the melting point of bulk water. FT-IR measurements suggest that the decrease in enthalpy change and interfacial free energy change with decreasing pore size reflect the similarity of the structures of both liquid and solid phases of water in smaller pores at lower temperatures.

Recovery of protein-losing enteropathy after living-donor lobar lung transplantation in primary pulmonary hypertension.

The patient investigated was a 43-year-old woman with primary pulmonary hypertension (PPH) and refractory protein-losing enteropathy (PLE). She underwent living-donor lobar lung transplantation (LDLLT), which led to remarkable improvement in both pulmonary hypertension and PLE. Although there have been no reports, to our knowledge, that have demonstrated PLE as a complication of PPH, the present case clearly shows how PLE could complicate PPH. In addition, and more importantly, hypo-proteinemia due to PLE should not necessarily be an exclusion criterion for lung transplantation when PPH is involved, because it could markedly improve after transplantation.

Oxidative stress provokes atherogenic changes in adipokine gene expression in 3T3-L1 adipocytes.

Increased oxidative stress has been associated with obesity-related disorders. In this study, we investigated how oxidative stress, in different ways of exposure, regulates gene expression of various adipokines in 3T3-L1 adipocytes. Exposure to 100-500microM H(2)O(2) for 10min, as well as exposure to 5-25mU/ml glucose oxidase for 18h, similarly decreased adiponectin, leptin, and resistin mRNAs, and increased plasminogen activator inhibitor-1 mRNA. Secretion levels of adipokines were also changed by oxidative stress in parallel with mRNA expression levels. Although a peak increase in plasminogen activator inhibitor-1 mRNA was achieved between 4 and 8h after exposure to H(2)O(2) for 10min, significant decreases in adiponectin and resistin mRNA were observed after 16h, while leptin mRNA was decreased earlier. Our results suggest that oxidative stress, even of short duration, has a significant impact on the regulation of various adipokine gene expressions favoring atherosclerosis.

Focal uptake on 18F-fluoro-2-deoxyglucose positron emission tomography images indicates cardiac involvement of sarcoidosis.

AIMS: To evaluate the value of (18)F-fluoro-2-deoxyglucose positron emission tomography ((18)F-FDG PET) in detecting cardiac sarcoidosis. METHODS AND RESULTS: Thirty-two patients with sarcoidosis and thirty controls were recruited. All subjects underwent cardiac (18)F-FDG PET after a 6 h fasting period, and subjects with sarcoidosis underwent blood testing, ECG, echocardiography, and (67)Ga and (99m)Tc-sestamibi (MIBI) scintigraphy. We classified (18)F-FDG PET images into four patterns ('none', 'diffuse', 'focal', and 'focal on diffuse') and found that all the control subjects exhibited either none (n=16) or diffuse (n=14) pattern. In contrast, fifteen subjects with sarcoidosis exhibited none, seven exhibited diffuse, eight exhibited focal, and two exhibited focal on diffuse patterns, with the prevalence of the focal and focal on diffuse patterns being significantly higher in the sarcoidosis group when compared with the control group (P<0.001). None of the 32 subjects with sarcoidosis exhibited abnormal findings on (67)Ga scintigraphy, and 4 exhibited abnormal findings on (99m)Tc-MIBI scintigraphy. CONCLUSION: Focal uptake of the heart on (18)F-FDG PET images is a characteristic feature of patients with sarcoidosis. Furthermore, (18)F-FDG PET has the potential to detect cardiac sarcoidosis that cannot be diagnosed by (67)Ga or (99m)Tc-MIBI scintigraphy.

Addition of oral sildenafil to beraprost is a safe and effective therapeutic option for patients with pulmonary hypertension.

Although sildenafil, an oral phosphodiesterase type-5 inhibitor, may offer benefits in the pharmacological management of pulmonary hypertension (PH), safety and effectiveness have not been studied during coadministration with beraprost, an oral prostacyclin analogue. To address this issue, we administered oral beraprost (40 microg) on day 1 and beraprost (40 microg) plus sildenafil (25 mg) on days 2 to 6 patients with moderate to severe PH. Although sildenafil plus beraprost produced transient flushing in 2 of 6 patients, systemic hemodynamics and arterial and venous gas analyses were similar in comparisons between the 2 treatment groups. In contrast, sildenafil plus beraprost therapy resulted in a 2.2-fold greater reduction in mean pulmonary arterial pressure and a 1.6-fold greater reduction in pulmonary vascular resistance compared with beraprost alone, and reductions in these parameters persisted longer with combination therapy than with beraprost alone. Addition of oral sildenafil to beraprost appears to represent a safe and effective therapeutic option, at least in the acute phase, for patients with pulmonary hypertension.