Upstroke time is a more useful marker of atherosclerosis than percentage of mean arterial pressure for detecting coronary artery disease in subjects with a normal ankle-brachial index.

Upstroke time (UT) and percentage of mean arterial pressure (%MAP) at the ankle have been shown to serve as atherosclerotic markers. The purpose of this study was to directly compare the diagnostic accuracy of UT with that of %MAP for clinical coronary artery disease (CAD) in subjects with a normal ankle-brachial index (ABI) in both legs. We measured UT and %MAP in 1953 subjects with a normal ABI. The optimal cutoff values of UT and %MAP derived from a receiver operating characteristic (ROC) curve to diagnose CAD were 148 ms and 40.4%, respectively. Multivariable analyses revealed that both UT ≥ 148 ms (odds ratio [OR], 2.72; p < 0.001) and %MAP ≥ 40.4% (OR, 1.28; p = 0.003) were significantly associated with CAD. When the subjects were divided into four groups according to the cutoff values of UT and %MAP, there was no significant difference in the risk of CAD between subjects with UT ≥ 148 ms and %MAP < 40.4% and those with UT ≥ 148 ms and %MAP ≥ 40.4% (OR, 1.45; p = 0.09). ROC curve analyses revealed that the area under the curve value of UT was significantly higher than that of %MAP (0.69 vs. 0.53, p < 0.001). The addition of UT to traditional risk factors significantly improved the diagnostic accuracy for CAD (0.82 to 0.84, p = 0.004), whereas the addition of %MAP to traditional risk factors did not improve the diagnostic accuracy for CAD (0.82 to 0.82, p = 0.84). UT is more useful than %MAP for identifying individuals with CAD among those with a normal ABI.

A Body Shape Index as a Simple Anthropometric Marker of Abdominal Obesity and Risk of Cardiovascular Events.

BACKGROUND: A Body Shape Index (ABSI) has been reported to have associations with cardiovascular risk factors. However, there is no information on the association between ABSI and incidence of cardiovascular events. METHODS: We investigated the associations between ABSI and first major cardiovascular events (death from cardiovascular disease, nonfatal acute coronary syndrome, and nonfatal stroke) in 1857 subjects from the database of Flow-Mediated Dilation Japan registry and from Hiroshima University Vascular Function registry. RESULTS: The areas under the curves of ABSI to predict the first major cardiovascular events were superior to BMI (men: P=0.032, women: P=0.015) and waist circumference in women (men: P=0.078, women: P=0.002). The subjects were divided into two groups based on the cutoff value of ABSI for predicting first major cardiovascular events: a low ABSI group (<0.0822 in men and <0.0814 in women) and a high ABSI group (≥0.0822 in men and ≥0.0814 in women). During a median follow-up period of 41.6 months, 56 subjects died (23 from cardiovascular causes), 16 had nonfatal acute coronary syndrome, and 14 had nonfatal stroke. The Kaplan-Meier curves for first major cardiovascular events were significantly different between the two groups (men, P<0.001; women, P<0.001). Multivariate analysis revealed that high ABSI remained an independent predictor of first major cardiovascular events (men: hazard ratio, 2.33; 95% CI, 1.07 to 5.06; P=0.033; women: hazard ratio, 8.33; 95% CI, 1.06 to 65.49; P=0.044). CONCLUSIONS: High ABSI is independently associated with incidence of cardiovascular events. ABSI calculation should be performed for evaluation of risk of cardiovascular events.

Effects of BNT162b2 mRNA Covid-19 vaccine on vascular function.

The effects of Covid-19 vaccines on vascular function are still controversial. We evaluated the effects of BNT162b2 vaccine (BioNTech and Pfizer) on endothelial function assessed by flow-mediated vasodilation (FMD) and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation (NID). This study was a prospective observational study. A total of 23 medical staff at Hiroshima University Hospital were enrolled in this study. FMD and NID were measured before vaccination and two weeks and six months after the 2nd dose of vaccination. FMD was significantly smaller two weeks after the 2nd dose of vaccination than before vaccination (6.5±2.4% and 8.2±2.6%, p = 0.03). FMD was significantly larger at six months than at two weeks after the 2nd dose of vaccination (8.2±3.0% and 6.5±2.4%, p = 0.03). There was no significant difference between FMD before vaccination and that at six months after the 2nd dose of vaccination (8.2±2.6% to 8.2±3.0%, p = 0.96). NID values were similar before vaccination and at two weeks, and six months after vaccination (p = 0.89). The BNT162b2 Covid-19 vaccine temporally impaired endothelial function but not vascular smooth muscle function, and the impaired endothelial function returned to the baseline level within six months after vaccination.

Association of cumulative low-density lipoprotein cholesterol exposure with vascular function.

BACKGROUND: The relationship between cumulative low-density lipoprotein cholesterol (LDL-C) exposure and progression of atherosclerosis remains uncertain. OBJECTIVE: The aim of this study was to determine the relationship between cumulative LDL-C level and flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID) and the presence of plaque in the common carotid artery (CCA). METHODS: This was a cross-sectional study. We measured FMD in 8208 subjects, NID in 1822 subjects, and CCA plaque in 591 subjects who were not taking lipid-lowering drugs. The subjects were divided into four groups based on cumulative LDL-C exposure: <4000 mg·year/dL, 4000-4999 mg·year/dL, 5000-5999 mg·year/dL, and ≥6000 mg·year/dL. RESULTS: The odds ratio of the lower quartile of FMD in the cholesterol-year-score <4000 mg·year/dL group was significantly higher than the odds ratios in the other groups. The odds ratio of the lower quartile of NID in the <4000 mg·year/dL group was significantly higher than the odds ratios in the 5000-5999 mg·year/dL and ≥6000 mg·year/dL groups. The odds ratio of the prevalence of CCA plaque in the <4000 mg·year/dL group was significantly higher than that in the ≥6000 mg·year/dL group. CONCLUSIONS: Endothelial dysfunction occurred from cumulative LDL-C exposure of 4000 mg·year/dL, vascular smooth muscle dysfunction occurred from cumulative LDL-C exposure of 5000 mg·year/dL, and prevalence of CCA plaque occurred from cumulative LDL-C exposure of 6000 mg·year/dL. CLINICAL TRIAL REGISTRY INFORMATION: http://www.umin.ac.jp (UMIN000012950, UMIN000012951, and UMIN000012952, UMIN000003409).

Seasonal variations in endothelium-dependent flow-mediated vasodilation and endothelium-independent nitroglycerine-induced vasodilation.

Cardiovascular mortality has been shown to vary seasonally. However, it has not been determined whether vascular function is affected by the season. The purpose of this study was to investigate the associations of vascular function with season and outdoor temperature. Between April 2007 and March 2022, measurements of flow-mediated vasodilation (FMD) of the brachial artery as an index of endothelial function and nitroglycerine-induced vasodilation (NID) as an index of endothelium-independent vasodilation were performed in 2190 subjects. There was no significant seasonal difference in FMD (spring, 3.9 ± 3.1%; summer, 3.5 ± 3.0%; fall, 3.7 ± 3.0%; winter, 3.6 ± 3.2%; P = 0.14). There was no significant correlation between FMD and daily mean outdoor temperature (r = -0.02, P = 0.25). Multivariate analyses revealed that neither season (ß = -0.020, P = 0.31) nor outdoor temperature (ß = 0.005, P = 0.81) was significantly associated with FMD after adjustment for other confounding factors. There were significant seasonal differences in NID (spring, 12.8 ± 6.3%; summer, 12.0 ± 6.1%; fall, 11.7 ± 6.1%; winter, 12.3 ± 5.9%; P = 0.02). However, multivariate analysis revealed that there was no significant association between season and NID after adjustment for other confounding factors (ß = -0.012, P = 0.56). There was no significant correlation between NID and daily outdoor mean temperature (r = -0.03, P = 0.17). Multivariate analysis revealed that outdoor temperature was not significantly associated with NID (ß = -0.006, P = 0.78). There was no significant association of FMD or NID with season or outdoor temperature, suggesting that it is not necessary to take into account the effects of season and outdoor temperature on vascular function when interpreting the results of FMD and NID measurements. Public trials registry number: UMIN000039512.

Percentage of mean arterial pressure as a marker of atherosclerosis for detecting patients with coronary artery disease.

The percentage of mean arterial pressure (%MAP) is the height of the mean arterial waveform divided by the peak amplitude of the waveform of pulse volume recording. The purpose of this study was to determine whether the cutoff value of 45% for %MAP at the ankle, which is recommended for the diagnosis of lower extremity artery disease, in combination with ankle-brachial index (ABI) is useful for detecting patients with clinical coronary artery disease (CAD) and investigate the optimal cutoff value of %MAP to diagnose patients with CAD.　We measured ABI and %MAP in 2213 subjects　(mean age: 61.2 ± 15.5 years). Multivariate analysis revealed that %MAP ≥ 45% was significantly associated with a higher risk of CAD after adjusting for traditional cardiovascular risk factors (odds ratio [OR], 2.14; 95% confidence interval [CI], 1.43-3.21; p < 0.001). However, the association was no longer significant after adjusting for ABI (OR, 1.39; 95% CI, 0.83-2.33; p = 0.21), whereas ABI was significantly associated with CAD (OR, 0.98; 95% CI, 0.97-0.99; p = 0.005). The optimal cutoff value of %MAP derived from a receiver operating characteristic curve to diagnose CAD was 40.3%. Multivariate analysis revealed that %MAP ≥ 40.3% was significantly associated with a higher risk of CAD (OR, 1.63; 95% CI, 1.19-2.24; p = 0.002) independent of ABI (OR, 0.98; 95% CI, 0.97-0.99; p = 0.002). The cutoff value of 40.3%, but not 45%, for %MAP may be useful for detecting patients with advanced atherosclerosis and for cardiovascular risk assessment independent of ABI. REGISTRATION INFORMATION: http://www.umin.ac.jp (University Hospital Medical Information Network Clinical Trials Registry) (UMIN000039512).

Role of Small Dense Low-density Lipoprotein Cholesterol in Cardiovascular Events in Patients with Coronary Artery Disease and Type 2 Diabetes Mellitus Receiving Statin Treatment.

AIM: There is little information on the relationships of serum small dense low-density lipoprotein cholesterol (sdLDL-C) levels and serum triglyceride (TG) levels with cardiovascular events in patients with coronary artery disease (CAD) and type 2 diabetes mellitus (DM) who are receiving statins. The aim of this study was to evaluate the relationships of serum TG levels and sdLDL-C levels as residual risks for cardiovascular events in patients with CAD and type 2 DM who were being treated with statins. METHODS: The subjects were divided into four groups based on TG levels and sdLDL-C levels: sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL, sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, and sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL. During a median follow-up period of 1419 days, cardiovascular events occurred in 34 patients. RESULTS: The incidences of cardiovascular events were significantly higher in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ＜150 mg/dL and in patients with sdLDL-C of ≥ 40.0 mg/dL and TG of ≥ 150 mg/dL, but not in patients with sdLDL-C of ＜40.0 mg/dL and TG of ≥ 150 mg/dL, than in patients with sdLDL-C of ＜40.0 mg/dL and TG of ＜150 mg/dL. CONCLUSIONS: Under the condition of treatment with statins, patients with CAD and type 2 DM who had sdLDL-C levels of ≥ 40.0 mg/dL had a high risk for cardiovascular events even though serum TG levels were controlled at ＜150 mg/dL.

Impact of overnight 1 mg dexamethasone on vascular function in patients with nonfunctioning adrenal adenomas.

The purpose of this study was to evaluate the effects of administration of overnight 1 mg dexamethasone on vascular function in patients with nonfunctioning adrenal adenomas (NFA). Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) were measured to assess vascular function in 22 patients with NFA who had hypertension and/or diabetes mellitus (DM) and 272 patients without adrenal incidentalomas who had hypertension and/or DM (control patients with hypertension and/or DM). FMD and NID were measured in the morning before and after administration of 1 mg of dexamethasone at 2300 h in 18 patients with NFA. There were no significant differences in FMD and NID between control patients with hypertension and/or DM and patients with NFA who had hypertension and/or DM (3.4 ± 2.8% vs. 2.9 ± 1.9% and 11.5 ± 5.7% vs. 11.4 ± 4.3%, P = 0.46, and P = 0.99, respectively). There were no significant differences in vascular function between control patients with hypertension and/or DM and patients with NFA who had hypertension and/or DM even after adjustment for cardiovascular risk factors. Overnight 1 mg dexamethasone increased FMD from 2.4 ± 1.9% to 5.3 ± 3.2% (P < 0.01) and increased NID from 12.1 ± 4.2% to 14.0 ± 2.8% (P < 0.01) in patients with NFA. The overnight 1 mg dexamethasone suppression test does not impair FMD and NID in patients with NFA. Decreases in circulating levels of cortisol may improve vascular function.Clinical Trial Registration: This study was approved by principal authorities and ethical issues in Japan (URL for Clinical Trial: http://www.umin.ac.jp/ctr/index.htm Registration Number for Clinical Trial: UMIN000039512).

KCNJ5 mutation is a predictor for recovery of endothelial function after adrenalectomy in patients with aldosterone-producing adenoma.

The relationship of KCNJ5 mutation with vascular function and vascular structure in aldosterone-producing adenoma (APA) patients before and after adrenalectomy remains unclear. The purpose of this study was to evaluate the influence of KCNJ5 mutation on vascular function and vascular structure in APA and the effects of adrenalectomy on vascular function and vascular structure in APA patients with and those without KCNJ5 mutation. Flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID), brachial artery intima-media thickness (IMT), and brachial-ankle pulse wave velocity (baPWV) were measured to assess vascular function and vascular structure in 46 APA patients with KCNJ5 mutation and 23 APA patients without KCNJ5 mutation and in 69 matched pairs of patients with essential hypertension (EHT). FMD, NID, brachial IMT and baPVW were evacuated before adrenalectomy and at 12 weeks after adrenalectomy in APA patients with KCNJ5 mutation and APA patients without KCNJ5 mutation. FMD and NID were significantly lower in APA patients than in patients with EHT. There was no significant difference in FMD or NID between patients with and those without KCNJ5 mutation. In APA patients with KCNJ5 mutation, FMD and NID after adrenalectomy were significantly higher than those before adrenalectomy. In APA patients without KCNJ5 mutation, only NID after adrenalectomy was significantly higher than that before adrenalectomy. Endothelial function in APA patients with KCNJ5 mutation was improved by adrenalectomy in the early postoperative period. KCNJ5 mutation is a predictor for early resolution of endothelial function by adrenalectomy. This study was approved by principal authorities and ethical issues in Japan (URL for Clinical Trial: http://www.umin.ac.jp/ctr/index.htm Registration Number for Clinical Trial: UMIN000003409).

Endothelial Function Is Preserved in Patients with Wild-Type Transthyretin Amyloid Cardiomyopathy.

Heart failure (HF) is associated with endothelial dysfunction. Vascular function per se plays an important role in cardiac function, whether it is a cause or consequence. However, there is no information on vascular function in patients with wild-type transthyretin amyloid cardiomyopathy (ATTRwt-CM). The purpose of this study was to evaluate vascular function in patients with ATTRwt-CM. We measured flow-mediated vasodilation (FMD) as an index of endothelial function and nitroglycerine-induced vasodilation (NID) as an index of vascular smooth muscle function and brachial artery intima-media thickness (bIMT) and brachial-ankle pulse wave velocity (baPWV) as indices of arterial stiffness in 22 patients with ATTRwt-CM and in 22 one-by-one matched control patients using vascular function confounding factors. FMD was significantly greater in patients with ATTRwt-CM than in the controls (5.4 ± 3.4% versus 3.5 ± 2.4%, p = 0.038) and the N-terminal pro-brain natriuretic peptide (NT-proBNP) level was significantly greater in patients with ATTRwt-CM than in the controls (2202 ± 1478 versus 470 ± 677 pg/mL, p < 0.001). There were no significant differences in NID, bIMT or baPWV between the two groups. There was a significant relationship between NT-proBNP and FMD in patients with ATTRwt-CM (r = 0.485, p = 0.022). NT-proBNP showed no significant relationships with NID, bIMT or baPWV. Conclusions: Endothelial function was preserved in patients with ATTRwt-CM. Patients with ATTRwt-CM may have compensatory effects with respect to endothelial function through elevation of BNP.

Deficiency of MicroRNA-23-27-24 Clusters Exhibits the Impairment of Myelination in the Central Nervous System.

Several microRNAs (miRNAs), including miR-23 and miR-27a have been reportedly involved in regulating myelination in the central nervous system. Although miR-23 and miR-27a form clusters in vivo and the clustered miRNAs are known to perform complementary functions, the role of these miRNA clusters in myelination has not been studied. To investigate the role of miR-23-27-24 clusters in myelination, we generated miR-23-27-24 cluster knockout mice and evaluated myelination in the brain and spinal cord. Our results showed that 10-week-old knockout mice had reduced motor function in the hanging wire test compared to the wild-type mice. At 4 weeks, 10 weeks, and 12 months of age, knockout mice showed reduced myelination compared to wild-type mice. The expression levels of myelin basic protein and myelin proteolipid protein were also significantly lower in the knockout mice compared to the wild-type mice. Although differentiation of oligodendrocyte progenitor cells to oligodendrocytes was not inhibited in the knockout mice, the percentage of oligodendrocytes expressing myelin basic protein was significantly lower in 4-week-old knockout mice than that in wild-type mice. Proteome analysis and western blotting showed increased expression of leucine-zipper-like transcription regulator 1 (LZTR1) and decreased expression of R-RAS and phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) in the knockout mice. In summary, loss of miR-23-27-24 clusters reduces myelination and compromises motor functions in mice. Further, LZTR1, which regulates R-RAS upstream of the ERK1/2 pathway, a signal that promotes myelination, has been identified as a novel target of the miR-23-27-24 cluster in this study.

Effect of exposure to radiation caused by an atomic bomb on endothelial function in atomic bomb survivors.

Background: The purpose of this study was to evaluate the effects of exposure to radiation caused by an atomic bomb in atomic bomb survivors on vascular function and vascular structure and to evaluate the relationships of radiation dose from the atomic bomb with vascular function and vascular structure in atomic bomb survivors. Methods: Flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID) as indices of vascular function, brachial-ankle pulse wave velocity (baPWV) as an index of vascular function and vascular structure, and brachial artery intima-media thickness (IMT) as an index of vascular structure were measured in 131 atomic bomb survivors and 1,153 control subjects who were not exposed to the atomic bomb. Ten of the 131 atomic bomb survivors with estimated radiation dose in a cohort study of Atomic Bomb Survivors in Hiroshima were enrolled in the study to evaluate the relationships of radiation dose from the atomic bomb with vascular function and vascular structure. Results: There was no significant difference in FMD, NID, baPWV, or brachial artery IMT between control subjects and atomic bomb survivors. After adjustment of confounding factors, there was still no significant difference in FMD, NID, baPWV, or brachial artery IMT between control subjects and atomic bomb survivors. Radiation dose from the atomic bomb was negatively correlated with FMD (ρ = -0.73, P = 0.02), whereas radiation dose was not correlated with NID, baPWV or brachial artery IMT. Conclusion: There were no significant differences in vascular function and vascular structure between control subjects and atomic bomb survivors. Radiation dose from the atomic bomb might be negatively correlated with endothelial function.

Foramen Magnum Decompression with Outer Dura Matter Layer Resection for Chiari Type I Malformation: Factors Correlated with Syrinx Reduction.

STUDY DESIGN: A retrospective cohort study. PURPOSE: We aimed to investigate the surgical results of foramen magnum decompression (FMD) to identify the potential factors associated with syrinx reduction in Chiari malformation type I (CMI). OVERVIEW OF LITERATURE: The predictive value of preoperative factors for syrinx reduction in patients with CMI remains debatable. METHODS: We enrolled patients who underwent microscopic FMD with outer dural layer resection for CMI. The distance from the tip of the cerebellar tonsil to the C2 vertebral endplate on sagittal magnetic resonance imaging (MRI) was defined as the tonsillar distance (TD). Patients who showed a >20% syrinx diameter reduction on the 1-year follow-up MRI were defined as the syrinx reduction group while the others were categorized in the syrinx nonreduction group. Patients with syringomyelia were categorized into the clinically improved and unimproved groups using the Chicago Chiari Outcome Scale. The imaging and clinical parameters were evaluated pre- and postoperatively. RESULTS: This study included 25 patients of whom 19 (76.0%) had syringomyelia. At the 1-year follow-up, the syrinx diameter had decreased in 11 patients (57.8%). The increased TD significantly differed between the syrinx reduction and nonreduction groups. At the 1-year follow-up, 12 and seven patients with syringomyelia were categorized into the clinically improved and unimproved groups, respectively. The clinically improved and unimproved groups showed significant differences in the mean age and increased TD. CONCLUSIONS: Postoperative syrinx reduction was significantly correlated with the upward shifting of the cerebellar tonsil in patients with CMI. Our quantitative evaluation of the alterations in hindbrain position after FMD was easily performed and reflects the clinical outcomes.

The prevalence of cardiovascular disease is higher in patients with bilateral low ankle-brachial index than in patients with unilateral low ankle-brachial index.

BACKGROUND AND AIMS: Ankle-brachial index (ABI) has been used as a vascular marker of atherosclerosis for cardiovascular risk assessment. However, it is unclear whether there is a difference in cardiovascular risk between patients with low ABI (<1.00) in one leg (unilateral low ABI) and patients with low ABIs in both legs (bilateral low ABI). Therefore, we investigated the associations of cardiovascular disease (CVD) with unilateral low ABI and bilateral low ABI to determine whether cardiovascular risk is higher in patients with bilateral low ABI than in patients with unilateral low ABI. METHODS: We measured ABI in 2226 subjects. RESULTS: The prevalence of CVD was higher in patients with bilateral low ABI than in individuals with normal ABI (1.00-1.40) and patients with unilateral low ABI (49.2%, 25.7% and 17.0%, respectively; p < 0.001). Multivariate analysis revealed that bilateral low ABI was significantly associated with an increased risk of CVD (OR, 2.30; 95% CI, 1.16 to 4.54; p = 0.02), whereas there was no significant association between unilateral low ABI and CVD (OR, 0.83; 95% CI, 0.47 to 1.46; p = 0.51). Propensity score matching analysis showed that the prevalence of CVD was significantly higher in patients with bilateral low ABI than in patients with unilateral low ABI (45.5% vs. 27.3%, p = 0.02). CONCLUSIONS: Cardiovascular risk may be higher in patients with bilateral low ABI than in patients with unilateral low ABI. More attention should be paid to whether a low ABI is present in one leg or in both legs for more precise cardiovascular risk assessment.

Differences between spinal cord injury and cervical compressive myelopathy in intramedullary high-intensity lesions on T2-weighted magnetic resonance imaging: A retrospective study.

Increases in aging populations have raised the number of patients with cervical spinal cord injury (SCI) without fractures due to compression of the cervical spinal cord. In such patients, it is necessary to clarify whether SCI or cervical compressive myelopathy (CCM) is the cause of disability after trauma. This study aimed to clarify the differences in magnetic resonance imaging (MRI) features between SCI and CCM. Overall, 60 SCI patients and 60 CCM patients with intramedullary high-intensity lesions on T2-weighted MRI were included in this study. The longitudinal lengths of the intramedullary T2 high-intensity lesions were measured using sagittal MRI sections. Snake-eye appearance on axial sections was assessed as a characteristic finding of CCM. The T2 values of the high-intensity lesions and normal spinal cords at the first thoracic vertebra level were measured, and the contrast ratio was calculated using these values. The longitudinal length of T2 high-intensity lesions was significantly longer in SCI patients than in CCM patients. Snake-eye appearance was found in 26 of the 60 CCM patients, but not in SCI patients. On both the sagittal and axial images, the contrast ratio was significantly higher in the SCI group than in the CCM group. Based on these results, a diagnostic scale was created. This scale made it possible to distinguish between SCI and CCM with approximately 90% accuracy.

Comparison of the electrophysiological characteristics of tight filum terminale and tethered cord syndrome.

PURPOSE: This study aims to characterize tight filum terminale (TFT) in motor evoked potential (MEP) testing by comparing TFT patients with both tethered cord syndrome (TCS) patients and healthy subjects. METHODS: Fifty TFT patients, 18 TCS patients, and 35 healthy volunteers participated in this study. We recorded MEPs following transcranial magnetic stimulation from the bilateral abductor hallucis muscles as well as compound muscle action potentials and F-waves evoked by electrical stimulation of the tibial nerve from the bilateral abductor pollicis brevis muscles. The peripheral conduction time (PCT) was calculated from the latency of the compound action potential and F-wave. Furthermore, the central motor conduction time (CMCT) was calculated by subtracting PCT from MEP latency. RESULTS: TFT and TCS patients had a significantly longer MEP latency than healthy subjects. PCT in TFT patients was significantly longer than those in TCS patients or healthy subjects. Using the cutoff values for PCT, we were able to diagnose patients with TFT patients with a sensitivity of 72.0% and a specificity of 91.4%. CONCLUSION: Prolonged PCT in the MEP test may be a useful indicator for TFT and suggests that MEP may be used as an adjunct diagnostic tool for TFT.

Relationship of Daily Coffee Intake with Vascular Function in Patients with Hypertension.

We evaluated the relationship of daily coffee intake with endothelial function assessed by flow-mediated vasodilation and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation in patients with hypertension. A total of 462 patients with hypertension were enrolled in this cross-sectional study. First, we divided the subjects into two groups based on information on daily coffee intake: no coffee group and coffee group. The median coffee intake was two cups per day in the coffee group. There were significant differences in both flow-mediated vasodilation (2.6 ± 2.8% in the no coffee group vs. 3.3 ± 2.9% in the coffee group, p = 0.04) and nitroglycerine-induced vasodilation (9.6 ± 5.5% in the no coffee group vs. 11.3 ± 5.4% in the coffee group, p = 0.02) between the two groups. After adjustment for confounding factors, the odds ratio for endothelial dysfunction (OR: 0.55, 95% CI: 0.32-0.95) and the odds ratio for vascular smooth muscle dysfunction (OR: 0.50, 95% CI: 0.28-0.89) were significantly lower in the coffee group than in the no coffee group. Next, we assessed the relationship of the amount of daily coffee intake with vascular function. Cubic spline curves revealed that patients with hypertension who drank half a cup to 2.5 cups of coffee per day had lower odds ratios for endothelial dysfunction assessed by flow-mediated vasodilation and vascular smooth muscle dysfunction assessed by nitroglycerine-induced vasodilation. Appropriate daily coffee intake might have beneficial effects on endothelial function and vascular smooth muscle function in patients with hypertension.

White blood cell count is not associated with flow-mediated vasodilation or nitroglycerine-induced vasodilation.

It is well known that white blood cell (WBC) count is an independent predictor of cardiovascular events. However, associations of WBC count and WBC subtypes with endothelial function assessed by flow-mediated vasodilation (FMD) and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation (NID) are unclear. The aim of this study was to determine the relationships of WBC count and WBC subtypes with vascular function assessed by FMD and NID. A total of 1351 subjects in whom FMD and NID had been measured were recruited from Hiroshima University Vascular Registry. Mean values were 3.7 ± 2.8% for FMD and 11.8 ± 5.9% for NID. WBC was not correlated with FMD or NID. NID was significantly correlated with lymphocytes in univariate analysis but not with other hematologic parameters. In multiple linear regression analyses, NID was not correlated with lymphocytes. In all subgroups including subgroups of age, gender, body mass index, hypertension, dyslipidemia, diabetes mellitus, smoking and tertile of WBC count, WBC count was not correlated with FMD or NID. WBC count and WBC subtypes were not associated with endothelial function assessed by FMD or vascular smooth muscle function assessed by NID. WBC count and vascular function assessed by FMD and NID may reflect different aspects of atherosclerosis.Clinical Trial Registration Information: URL for Clinical Trial: http://www.umin.ac.jp Registration Number for Clinical Trial: UMIN000039512.

Evaluation of intervertebral disc degeneration using T2 signal ratio on magnetic resonance imaging.

PURPOSE: Intervertebral disc degeneration is assessed clinically by magnetic resonance imaging (MRI). Although some quantitative evaluation methods for MRI under special imaging conditions have been reported, they are widely and generally difficult to use. The aim of this study is to determine if intervertebral disc degeneration can be assessed using the ratio of MRI T2 values of the disc to the spinal cord T2 values. METHODS: Signal ratio was calculated using the T2 signal intensity of the disc and the spinal cord on MRI under common conditions for a new assessment of disc degeneration. T2-weighted images of 100 patients undergoing MRI twice within a year under different imaging conditions, 1.5 T or less and 3.0 T, were used for the assessment. The T2 signal intensity was measured at the center of the discs at L2-3, L3-4, L4-5, L5-S1 and the spinal cord at T12 level. Signal ratio was calculated using these T2 signal intensity values. The ratio of the difference between the first and second values to the mean of the first and second values was calculated to confirm the equivalence of MRI assessments of disc degeneration in the same patient under different imaging conditions. RESULTS: The equivalence of values between the first MRI and the second MRI in the signal ratio was significantly higher than that in the T2 signal intensity. In addition, the signal ratio was negatively correlated with age and were significantly associated with Pfirrmann grade. CONCLUSIONS: By using the signal ratio, disc degeneration can be evaluated by MRI even under different imaging conditions.