Metal-free isotactic-specific radical polymerization of N-alkylacrylamides with 3,5-dimethylpyridine N-oxide : The effect of the N-substituent and solvent on the isotactic specificity

Radical polymerization of N-methylacrylamide (NMAAm), N-n-propylacrylamide, N-isopropylacrylamide (NIPAAm) and N-benzylacrylamide was investigated in CHCl3, CH2Cl2 and CH3CN, in the presence of 3,5-dimethylpyridine N-oxide (35DMPNO) to examine the effects of the N-substituent and the solvent on the isotactic specificity induced by 35DMPNO. With addition of 35DMPNO to radical polymerization of N-alkylacrylamides in CHCl3, isotactic specificity was significantly induced in NIPAAm polymerization but only slightly induced in NMAAm polymerization. Furthermore, mixed solvents of CH3CN and halomethanes such as CHCl3 and CH2Cl2 enhanced the ability of 35DMPNO to induce isotactic specificity, and poly(NIPAAm) with 74% meso dyad was obtained

Morphometric human embryonic brain features according to developmental stage

Objectives: The present study investigated linear, area, and volume measurements of human brain samples according to Carnegie stages (CS) in an attempt to select suitable morphometric features that reflect embryonic development. Methods: Using magnetic resonance imaging, we measured seven linear segments, three separate areas, and three regional volumes in 101 samples between CS13 and 23. Brain volume was determined via manual segmentation of the magnetic resonance image, whereby a formula was generated to estimate the volume of each linear measurement. Results: All parameters correlated with crown-rump length. Bitemporal length and mesencephalic height increased linearly according to the CS, and a high correlation between bitemporal length and both whole-brain (r=0.98) and prosencephalon (r=0.99) volumes was found when brain cavity volume was excluded. Conclusion: Morphometric data related to human embryonic stages are valuable for correcting and comparing sonographic data. The present approach may contribute to improvements in prenatal diagnostics by enabling the selection of more suitable measurements during early embryonic stages

Effect of ipragliflozin on carotid intima-media thickness in type 2 diabetes patients

Aims To examine the effects of a 24-month treatment with ipragliflozin on carotid intima-media thickness (IMT) in type 2 diabetes patients. Methods and results In this multicenter, prospective, randomized, open-label, and blinded-endpoint investigator-initiated clinical trial, adults with type 2 diabetes and haemoglobin A1C (HbA1c) of 6.0–10.0% (42–86 mmol/mol) were randomized equally to ipragliflozin (50 mg daily) and non-sodium-glucose cotransporter-2 (SGLT2) inhibitor use of standard-care (control group) for type 2 diabetes and were followed-up to 24 months. The primary endpoint was the change in mean common carotid artery IMT (CCA-IMT) from baseline to 24 months. A total of 482 patients were equally allocated to the ipragliflozin (N = 241) and control (N = 241) groups, and 464 patients (median age 68 years, female 31.7%, median type 2 diabetes duration 8 years, median HbA1c 7.3%) were included in the analyses. For the primary endpoint, the changes in the mean CCA-IMT from baseline to 24 months were 0.0013 [95% confidence interval (CI), −0.0155–0.0182] mm and 0.0015 (95% CI, −0.0155–0.0184) mm in the ipragliflozin and control groups, respectively, with an estimated group difference (ipragliflozin-control) of −0.0001 mm (95% CI, −0.0191–0.0189; P = 0.989). A group difference in HbA1c change at 24 months was also non-significant between the treatment groups [−0.1% (95% CI, −0.2–0.1); P = 0.359]. Conclusion Twenty-four months of ipragliflozin treatment did not affect carotid IMT status in patients with type 2 diabetes recruited in the PROTECT study, relative to the non-SGLT2 inhibitor-use standard care for type 2 diabetes

Longitudinal association among endothelial function, arterial stiffness and subclinical organ damage in hypertension

Objectives: To examine the longitudinal mutual association between endothelial dysfunction and arterial stiffness, and also to determine which of the two variables was more closely associated with the progression of subclinical organ damage. Methods: The brachial-ankle pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), estimated glomerular filtration rate, microalbuminuria and flow-mediated vasodilatation of the brachial artery (FMD) were measured three times at 1.5-year intervals in 674 Japanese patients receiving antihypertensive treatment. Results: The change of the baPWV during the study period was larger in the subjects with baseline FMD values in the lowest tertile as compared to those with baseline FMD values in the highest tertile. The change of the CIMT was smaller in the subjects with baseline baPWV values in the lowest tertile than in those with baseline baPWV values in the highest tertile. After the adjustment, the FMD value at the baseline was inversely associated with the baPWV at the end of the study period (beta = − 0.07, p = 0.01), although, the reverse association was not significant. The baPWV, but not the FMD value, at the baseline was associated with the CIMT (beta = 0.06, p = 0.04) measured at the end of the study period. Conclusions: In hypertension, endothelial dysfunction was associated with the progression of arterial stiffness, although the reverse association was not confirmed. The increased arterial stiffness rather than endothelial dysfunction may be more closely associated with the progression of atherosclerotic vascular damage, and the endothelial dysfunction-arterial stiffness-atherosclerosis continuum may be important in hypertension

Rationale and design of a multicenter randomized study for evaluating vascular function under uric acid control using the xanthine oxidase inhibitor, febuxostat : the PRIZE study

Background: Xanthine oxidase inhibitors are anti-hyperuricemic drugs that decrease serum uric acid levels by inhibiting its synthesis. Xanthine oxidase is also recognized as a pivotal enzyme in the production of oxidative stress. Excess oxidative stress induces endothelial dysfunction and inflammatory reactions in vascular systems, leading to atherosclerosis. Many experimental studies have suggested that xanthine oxidase inhibitors have anti-atherosclerotic effects by decreasing in vitro and in vivo oxidative stress. However, there is only limited evidence on the clinical implications of xanthine oxidase inhibitors on atherosclerotic cardiovascular disease in patients with hyperuricemia. We designed the PRIZE study to evaluate the effects of febuxostat on a surrogate marker of cardiovascular disease risk, ultrasonography-based intima-media thickness of the carotid artery in patients with hyperuricemia. Methods: The study is a multicenter, prospective, randomized, open-label and blinded-endpoint evaluation (PROBE) design. A total of 500 patients with asymptomatic hyperuricemia (uric acid >7.0 mg/dL) and carotid intima-media thickness ≥1.1 mm will be randomized centrally to receive either febuxostat (10–60 mg/day) or non-pharmacological treatment. Randomization is carried out using the dynamic allocation method stratified according to age (<65, ≥65 year), gender, presence or absence of diabetes mellitus, serum uric acid (<8.0, ≥8.0 mg/dL), and carotid intima-media thickness (<1.3, ≥1.3 mm). In addition to administering the study drug, we will also direct lifestyle modification in all participants, including advice on control of body weight, sleep, exercise and healthy diet. Carotid intima-media thickness will be evaluated using ultrasonography performed by skilled technicians at a central laboratory. Follow-up will be continued for 24 months. The primary endpoint is percentage change in mean intima-media thickness of the common carotid artery 24 months after baseline, measured by carotid ultrasound imaging. Conclusions: PRIZE will be the first study to provide important data on the effects of febuxostat on atherosclerosis in patients with asymptomatic hyperuricemia

Reduced reactive hyperemia of the brachial artery in diabetic patients assessed by repeated measurements : The FMD-J B study

Type 2 diabetes mellitus (T2DM) is a major cause of microvascular dysfunction. However, its effect on blood flow patterns during ischemic demand has not been adequately elucidated. In this study, we investigated the hypothesis that microvascular dysfunction in patients with T2DM manifests as brachial reactive hyperemia (BRH), defined as the ratio of peak blood flow velocities in a brachial artery before and after forearm cuff occlusion. The study enrolled 943 subjects (men, n = 152 [T2DM] and n = 371 [non-T2DM]; women, n = 107 [T2DM] and n = 313 [non-T2DM], respectively) with no history of cardiovascular disease. Semiautomatic measurements were obtained three times at 1.5-year intervals to confirm the reproducibility of factors involved in BRH for each sex. An age-adjusted mixed model demonstrated attenuated BRH in the presence of T2DM in both men (p = 0.022) and women (p = 0.031) throughout the study period. Post hoc analysis showed that the estimated BRH was significantly attenuated in patients with T2DM regardless of sex, except at baseline in women. In multivariate regression analysis, T2DM was a negative predictor of BRH at every measurement in men. For women, BRH was more strongly associated with alcohol consumption. Repeated measurements analysis revealed that T2DM was associated with attenuated postocclusion reactive hyperemia

Reliability of measurement of endothelial function across multiple institutions and establishment of reference values in Japanese

Aims: For the standardization of flow-mediated vasodilatation (FMD) assessment as a clinical tool, validation of its reliability across multiple institutions and the establishment of normal/reference values based on reliable data from multiple institutions are needed. Methods and results: In Study 1, assessment of FMD (scan recording and analysis) using an ultrasonographic semi-automatic measuring system (sFMD) was conducted at 18 participating institutions (sFMD-INST) (n = 981). All of the brachial arterial scans were also analyzed at a core laboratory (sFMD-COLB). After 111 subjects with inadequate sFMD recordings were excluded (n = 880), the correlation between the sFMD-INST and sFMD-COLB improved from R = 0.725 to R = 0.838 (p < 0.001). In Study 2, based on good-quality sFMD data obtained from 6660 subjects without cardiovascular disease (CVD) and 729 subjects with CVD from 27 institutions, reference values of sFMD are proposed by the Framingham risk score (FRS)-based risk categories and according to gender and age. The receiver-operating characteristic curve analysis revealed a significant power of sFMD values in reference ranges to discriminate between subjects with and without CVD (e.g., area under curve = 0.64 in the FRS-low risk group). Conclusions: When the analysis was limited to cases with clear sFMD recordings, the reliability of the sFMD assessment (scan and its analysis) conducted in individual institutions appeared to be acceptable. Reference sFMD values (lower cuff occlusion) for the Japanese population are proposed based on reliable data derived from multiple institutions, and the reference values may identify patients without advanced vascular damage

Longitudinal association among endothelial function, arterial stiffness and subclinical organ damage in hypertension

ObjectivesTo examine the longitudinal mutual association between endothelial dysfunction and arterial stiffness, and also to determine which of the two variables was more closely associated with the progression of subclinical organ damage.MethodsThe brachial-ankle pulse wave velocity (baPWV), carotid intima-media thickness (CIMT), estimated glomerular filtration rate, microalbuminuria and flow-mediated vasodilatation of the brachial artery (FMD) were measured three times at 1.5-year intervals in 674 Japanese patients receiving antihypertensive treatment.ResultsThe change of the baPWV during the study period was larger in the subjects with baseline FMD values in the lowest tertile as compared to those with baseline FMD values in the highest tertile. The change of the CIMT was smaller in the subjects with baseline baPWV values in the lowest tertile than in those with baseline baPWV values in the highest tertile. After the adjustment, the FMD value at the baseline was inversely associated with the baPWV at the end of the study period (beta = − 0.07, p = 0.01), although, the reverse association was not significant. The baPWV, but not the FMD value, at the baseline was associated with the CIMT (beta = 0.06, p = 0.04) measured at the end of the study period.ConclusionsIn hypertension, endothelial dysfunction was associated with the progression of arterial stiffness, although the reverse association was not confirmed. The increased arterial stiffness rather than endothelial dysfunction may be more closely associated with the progression of atherosclerotic vascular damage, and the endothelial dysfunction-arterial stiffness-atherosclerosis continuum may be important in hypertension

Febuxostat and carotid atherosclerosis in asymptomatic hyperuricemia

Background An elevated level of serum uric acid (SUA) is associated with an increased risk of cardiovascular disease. Pharmacological intervention with urate-lowering agents, such as the conventional purine analogue xanthine oxidase (XO) inhibitor, allopurinol, has been used widely for a long period of time in clinical practice to reduce SUA levels. Febuxostat, a novel non-purine selective inhibitor of XO, has higher potency for inhibition of XO activity and greater urate-lowering efficacy than conventional allopurinol. However, clinical evidence regarding the effects of febuxostat on atherosclerosis is lacking. The purpose of the study was to test whether treatment with febuxostat delays carotid intima-media thickness (IMT) progression in patients with asymptomatic hyperuricemia. Methods and findings The study was a multicenter, prospective, randomized, open-label, blinded-endpoint clinical trial undertaken at 48 sites throughout Japan between May 2014 and August 2018. Adults with both asymptomatic hyperuricemia (SUA >7.0 mg/dL) and maximum IMT of the common carotid artery (CCA) ≥1.1 mm at screening were allocated equally using a central web system to receive either dose-titrated febuxostat (10–60 mg daily) or as a control-arm, non-pharmacological lifestyle modification for hyperuricemia, such as a healthy diet and exercise therapy. Of the 514 enrolled participants, 31 were excluded from the analysis, with the remaining 483 people (mean age 69.1 years [standard deviation 10.4 years], female 19.7%) included in the primary analysis (febuxostat group, 239; control group, 244), based on a modified intention-to-treat principal. The carotid IMT images were recorded by a single sonographer at each site and read in a treatment-blinded manner by a single analyzer at a central core laboratory. The primary endpoint was the percentage change from baseline to 24 months in mean IMT of the CCA, determined by analysis of covariance using the allocation adjustment factors (age, gender, history of type 2 diabetes, baseline SUA, and baseline maximum IMT of the CCA) as the covariates. Key secondary endpoints included changes in other carotid ultrasonographic parameters and SUA and the incidence of clinical events. The mean values (± standard deviation) of CCA-IMT were 0.825 mm ± 0.173 mm in the febuxostat group and 0.832 mm ± 0.175 mm in the control group (mean between-group difference [febuxostat − control], −0.007 mm [95% confidence interval (CI) −0.039 mm to 0.024 mm; P = 0.65]) at baseline; 0.832 mm ± 0.182 mm in the febuxostat group and 0.848 mm ± 0.176 mm in the control group (mean between-group difference, −0.016 mm [95% CI −0.051 mm to 0.019 mm; P = 0.37]) at 24 months. Compared with the control group, febuxostat had no significant effect on the primary endpoint (mean percentage change 1.2% [95% CI −0.6% to 3.0%] in the febuxostat group (n = 207) versus 1.4% [95% CI −0.5% to 3.3%] in the control group (n = 193); mean between-group difference, −0.2% [95% CI −2.3% to 1.9%; P = 0.83]). Febuxostat also had no effect on the other carotid ultrasonographic parameters. The mean baseline values of SUA were comparable between the two groups (febuxostat, 7.76 mg/dL ± 0.98 mg/dL versus control, 7.73 mg/dL ± 1.04 mg/dL; mean between-group difference, 0.03 mg/dL [95% CI −0.15 mg/dL to 0.21 mg/dL; P = 0.75]). The mean value of SUA at 24 months was significantly lower in the febuxostat group than in the control group (febuxostat, 4.66 mg/dL ± 1.27 mg/dL versus control, 7.28 mg/dL ± 1.27 mg/dL; mean between-group difference, −2.62 mg/dL [95% CI −2.86 mg/dL to −2.38 mg/dL; P < 0.001]). Episodes of gout arthritis occurred only in the control group (4 patients [1.6%]). There were three deaths in the febuxostat group and seven in the control group during follow-up. A limitation of the study was the study design, as it was not a placebo-controlled trial, had a relatively small sample size and a short intervention period, and only enrolled Japanese patients with asymptomatic hyperuricemia. Conclusions In Japanese patients with asymptomatic hyperuricemia, 24 months of febuxostat treatment did not delay carotid atherosclerosis progression, compared with non-pharmacological care. These findings do not support the use of febuxostat for delaying carotid atherosclerosis in this population

Rationale and design of a multicenter randomized controlled study to evaluate the preventive effect of ipragliflozin on carotid atherosclerosis : the PROTECT study

Background: Type 2 diabetes mellitus is associated strongly with an increased risk of micro- and macro-vascular complications, leading to impaired quality of life and shortened life expectancy. In addition to appropriate glycemic control, multi-factorial intervention for a wide range of risk factors, such as hypertension and dyslipidemia, is crucial for management of diabetes. A recent cardiovascular outcome trial in diabetes patients with higher cardiovascular risk demonstrated that a SGLT2 inhibitor markedly reduced mortality, but not macro-vascular events. However, to date there is no clinical evidence regarding the therapeutic effects of SGLT2 inhibitors on arteriosclerosis. The ongoing PROTECT trial was designed to assess whether the SGLT2 inhibitors, ipragliflozin, prevented progression of carotid intima-media thickness in Japanese patients with type 2 diabetes mellitus. Methods: A total of 480 participants with type 2 diabetes mellitus with a HbA1c between 6 and 10 % despite receiving diet/exercise therapy and/or standard anti-diabetic agents for at least 3 months, will be randomized systematically (1:1) into either ipragliflozin or control (continuation of conventional therapy) groups. After randomization, ipragliflozin (50–100 mg once daily) will be added on to the background therapy in participants assigned to the ipragliflozin group. The primary endpoint of the study is the change in mean intima-media thickness of the common carotid artery from baseline to 24 months. Images of carotid intima-media thickness will be analyzed at a central core laboratory in a blinded manner. The key secondary endpoints include the change from baseline in other parameters of carotid intima-media thickness, various metabolic parameters, and renal function. Other cardiovascular functional tests are also planned for several sub-studies. Discussion: The PROTECT study is the first to assess the preventive effect of ipragliflozin on progression of carotid atherosclerosis using carotid intima-media thickness as a surrogate marker. The study has potential to clarify the protective effects of ipragliflozin on atherosclerosis