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Featured researches published by Takeshi Takami.


Hypertension Research | 2005

The Japanese trial to assess optimal systolic blood pressure in elderly hypertensive patients (JATOS): Protocol, patient characteristics, and blood pressure during the first 12 months

Yoshio Goto; Masao Ishii; Takao Saruta; Tadashi Kawakami; Kanemi Kawabe; Toshio Ogihara; Yuhei Kawano; Kenjiro Kikuchi; Kazuaki Shimamoto; Masayuki Sakurai; Makoto Sugahara; Sadayoshi Ito; Hiroaki Matsuoka; Yoshihiko Sato; Seishiro Ono; Satoshi Umemura; Yoshiro Shiota; Masaaki Miyagawa; Kenichi Doniwa; Genjiro Kimura; Yutaka Tada; Masayoshi Nakao; Takeshi Takami; Mikio Arita; Mitunori Okamoto; Kunio Hiwada; Masunori Matsuzaki; Akira Takeshita; Kozaburo Abe; Takashi Honda

The benefits of a systolic blood pressure (BP) below 150–160 mmHg are well established; whether a systolic BP of less than 140 mmHg provides additional benefits remains controversial. This study was designed to compare the 2-year effect of a strict treatment to maintain systolic BP below 140 mmHg (group A) and that of a mild treatment to maintain systolic BP at between 140 and below 160 mmHg (group B). The study design followed the Prospective Randomized Open Blinded End-point (PROBE) study. The subjects were elderly patients (65–85 years old) who consistently had a systolic BP of 160 mmHg or higher. The baseline drug was efonidipine hydrochloride (efonidipine), a long-acting dihydropiridine calcium antagonist. The primary endpoints were stroke, cardiac disease, vascular disease, and renal failure. After a run-in period of 2 to 4 weeks, 2,165 patients were assigned to group A and 2,155 patients to group B. There were no significant differences between the groups in sex, age, baseline BP, or other cardiovascular risk factors. The systolic BP was 7.2 mmHg lower (p<0.0001) and the diastolic BP 2.4 mmHg lower (p<0.0001) in group A than in group B after 12 months of treatment. As of this interim analysis, primary endpoints have occurred in 87 patients (stroke in 58 patients, cardiac disease in 27 patients, occlusive arterial disease in 1 patient, and renal failure in 1 patient). Five patients have died of stroke and 2 patients of myocardial infarction. The primary-endpoint-related morbidity rate was 20.9/1,000 patient-years, and the mortality rate was 1.7/1,000 patient-years. Currently available results indicate that this study, one of the largest randomized trials of antihypertensive therapy in elderly patients in Japan, was conducted safely. The final results are expected to provide important and practical information for the management of hypertension in elderly patients.The benefits of a systolic blood pressure (BP) below 150–160 mmHg are well established; whether a systolic BP of less than 140 mmHg provides additional benefits remains controversial. This study was designed to compare the 2-year effect of a strict treatment to maintain systolic BP below 140 mmHg (group A) and that of a mild treatment to maintain systolic BP at between 140 and below 160 mmHg (group B). The study design followed the Prospective Randomized Open Blinded End-point (PROBE) study. The subjects were elderly patients (65–85 years old) who consistently had a systolic BP of 160 mmHg or higher. The baseline drug was efonidipine hydrochloride (efonidipine), a long-acting dihydropiridine calcium antagonist. The primary endpoints were stroke, cardiac disease, vascular disease, and renal failure. After a run-in period of 2 to 4 weeks, 2,165 patients were assigned to group A and 2,155 patients to group B. There were no significant differences between the groups in sex, age, baseline BP, or other cardiovascular risk factors. The systolic BP was 7.2 mmHg lower (p<0.0001) and the diastolic BP 2.4 mmHg lower (p<0.0001) in group A than in group B after 12 months of treatment. As of this interim analysis, primary endpoints have occurred in 87 patients (stroke in 58 patients, cardiac disease in 27 patients, occlusive arterial disease in 1 patient, and renal failure in 1 patient). Five patients have died of stroke and 2 patients of myocardial infarction. The primary-endpoint-related morbidity rate was 20.9/1,000 patient-years, and the mortality rate was 1.7/1,000 patient-years. Currently available results indicate that this study, one of the largest randomized trials of antihypertensive therapy in elderly patients in Japan, was conducted safely. The final results are expected to provide important and practical information for the management of hypertension in elderly patients.


Vascular Health and Risk Management | 2011

Effects of smoking cessation on central blood pressure and arterial stiffness

Takeshi Takami; Yoshihiko Saito

Purpose: Smoking affects arterial stiffness, thus causing an elevation in central blood pressure (CBP). The present study was designed to examine whether smoking cessation treatment improved CBP and arterial stiffness. Patients and methods: We conducted an observational study of 70 patients receiving smoking cessation treatment. Before and 60 weeks after the start of a 12-week varenicline treatment, we measured brachial blood pressure, CBP, brachial-ankle pulse wave velocity (baPWV), normalized radial augmentation index (rAIx@75), left ventricular weight, and left ventricular diastolic function of each patient. The data were compared between the patients who succeeded in quitting smoking (smoking cessation group; n = 37) and those who failed to quit smoking (smoking group; n = 33). Results: Baseline characteristics were similar in both groups. Brachial blood pressure remained unchanged in both groups. CBP, baPWV, and rAIx@75 decreased significantly in the smoking cessation group, while these parameters showed no significant change in the smoking group. Thus, CBP, baPWV, and rAIx@75 showed greater decrease in the smoking cessation group than in the smoking group (CBP, −7.1 ± 1.4 mmHg vs 1.2 ± 2.7 mmHg; P < 0.01; baPWV, −204 ± 64 cm/s vs −43 ± 72 cm/s; P < 0.01; rAIx@75, −6.4 ± 2.8% vs −1.0 ± 3.9%; P < 0.01). Left ventricular weight and left ventricular diastolic function remained unchanged in both groups. Conclusion: Patients in the smoking cessation group showed significant improvement in CBP, baPWV, and rAIx@75. These results indicate that smoking cessation can improve arterial stiffness and CBP.


Clinical and Experimental Hypertension | 2003

Effects of Calcium Channel Antagonists on Left Ventricular Hypertrophy and Diastolic Function in Patients with Essential Hypertension

Takeshi Takami; Minori Shigematsu

Hypertensive patients characteristically exhibit left ventricular (LV) hypertrophy and diastolic dysfunction. The effects of antihypertensive agents on LV hypertrophy and diastolic dysfunction do not always correlate with the degree of blood pressure reduction, but their effects on the sympathetic nervous system and renin–angiotensin system (RA system) are thought to be important. We investigated the effects of amlodipine and cilnidipine, N‐ and L‐type calcium channel antagonists that suppress both blood pressure elevation and sympathetic activities, on LV hypertrophy and diastolic function. Patients with essential hypertension were randomly assigned to receive either amlodipine, cilnidipine or nifedipine CR (which does not block N‐type calcium channels) for 6 months. The LV mass index was determined using M‐mode echocardiography. The E/A ratio, i.e., the ratio of maximum amplitude between the early diastolic wave (E wave) and the atrial systolic wave (A wave) in the LV inflow pattern, and the deceleration time for the E wave were determined using pulse Doppler echocardiography. Systolic and diastolic blood pressures significantly decreased from the baseline values in all three groups, with no significant differences among the groups. The LV mass index had significantly decreased when it was evaluated 3 months after the initiation of treatment in the cilnidipine group and when it was evaluated 6 months after the initiation of treatment in the amlodipine group; only a slight decrease was observed in the nifedipine CR group. A significant decrease in the deceleration time and a significant increase in the E/A ratio were observed after 3 months of treatment in the cilnidipine and amlodipine groups but not in the nifedipine CR group. Thus, the effects of long‐acting calcium channel antagonists on hypertensive LV hypertrophy and LV diastolic function varied from one antagonist to the other. Left ventricular hypertrophy and diastolic function improved in the cilnidipine and amlodipine groups, but not in the nifedipine CR group. These results indicate that the suppression of sympathetic nerve activity by the blockade of N‐type calcium channels contributes to the improvement of LV hypertrophy and diastolic function.


Cellular Immunology | 1975

Induction of anti-hapten antibody response by hapten-isologous carrier conjugate: II. Specificity of hapten-reactive helper T cells

Uki Yamashita; Takeshi Takami; Masayasu Kitagawa

Abstract Anti-hapten antibody production was elicited by the immunization of hapten-isologous carrier conjugate (PAB-MGG) in mice. Spleen and lymph node cells taken from these primed mice could demonstrate their helper activity for anti-DNP antibody production when transferred intravenously into 600R X-irradiated recipient mice along with DNP-primed B cells and the double hapten conjugated carrier, DNP-MGG-PAB. Isologous carrier (MGG)-primed cells could not demonstrate this helper activity. Accordingly, helper cells reactive for a haptenic group are considered to develop by the immunization of hapten-isologous carrier conjugate. Hapten-reactive helper activity was also induced by the immunization of other hapten-isologous carrier conjugates, e.g., MAB-MGG, PABS-MGG or PAB-MSA. These hapten-reactive helper cells were T lymphocytes, as the helper activity of PAB-MGG-primed cells was completely abolished by in vivo ATS-treatment. Helper activity of PAB-MGG-primed cells for DNP-primed B cells was also demonstrated through the double hapten conjugated heterologous carrier DNP-HGG-PAB to be the same as with DNP-MGG-PAB, but weakly through DNP-KLH-PAB. As HGG but not KLH resembles MGG in composition, almost all hapten-reactive helper T cells can be considered to recognize not only haptenic groups but also physicochemical properties of the hapten-conjugated carrier site. However, these helper T cells could discriminate structural differences among related haptenic groups, because PAB-MGG-primed cells clearly responded to DNP-MGG-PAB to demonstrate their helper activity for DNP-primed B cells, but responded only weakly to DNP-MGG-PABS or DNP-MGG-MAB. When the specificity restrictions of T and B cells to the same haptenic group were compared by responsiveness measured after the antigenic stimulation (B cell function by anti-hapten antibody production and T cell function by helper activity), differences were noted, as PAB-MGG-primed T cells could respond not only to DNP-MGG-PAB but also fairly well to DNP-MGG-MAB to demonstrate their helper activity, but PAB-MGG-primed B cells responded to only PAB-MGG. Thus, hapten specificity appears to be much more restricted for B cells than T cells. The difference of this responsivity between B cells and helper T cells was thought to derive from the specificity difference of B cell and helper T cell receptors rather than from any sensitivity differences of the experimental procedure. The differences in the specificity restrictions of receptors of B and helper T cells were discussed in the light of hapten-specificity.


Cellular Immunology | 1976

Immune maturation of T lymphocytes: Sequential changes in the functional specificity and apparent affinity of hapten-reactive helper T cells during an immune response

Uki Yamashita; Toshiyuki Hamaoka; Takeshi Takami; Masayasu Kitagawa

Abstract The maturation of helper T lymphocytes during an immune response was studied with respect to sequential changes in the functional specificity and affinity toward certain antigens. Protein-carrier (BαA)-reactive helper T cells obtained after a relatively long priming period were effectively stimulated by relatively lower doses of antigen than shortly primed helper T lymphocytes. When hapten (PAB)-reactive helper T lymphocytes were utilized as a model of helper T cells, reactivity also increased progressively to smaller concentrations of PAB-conjugates at successive intervals after primary immunization. Concomitantly, the cross-reactivity of PAB-reactive helper T cells to structurally related MAB- or OAB-determinants also decreased. Moreover, the PAB-reactive helper T cells of the relatively longer priming period were very susceptible to tolerance induction upon treatment with PAB- d -GL, whereas the reactivity of those helper T cells of the relatively shorter priming period was not abolished by this treatment. These results clearly indicate that there are qualitative changes in the helper T lymphocyte population during an immune response, and that this represents the sequential development or selection of helper T lymphocytes of higher specificity and apparent affinity to a corresponding antigenic determinant.


Drug Design Development and Therapy | 2013

Azelnidipine plus olmesartan versus amlodipine plus olmesartan on arterial stiffness and cardiac function in hypertensive patients: a randomized trial

Takeshi Takami; Yoshihiko Saito

Purpose To compare the long-term effects of olmesartan combined with either azelnidipine or amlodipine on central blood pressure (CBP), left ventricular (LV) mass index (LVMI), LV diastolic function (e′ velocity, E/e′ ratio, E/A ratio) and arterial stiffness (brachial-ankle pulse wave velocity [baPWV] and augmentation index normalized for a heart rate of 75 bpm [AIx]). Patients and methods Patients with systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg received olmesartan monotherapy (20 mg/day) for 12 weeks. They were then randomly assigned to fixed-dose add-on therapy with azelnidipine (16 mg/day; n = 26) or amlodipine (5 mg/day; n = 26) for a further 2 years. CBP, LVMI, e′ velocity, E/e′ ratio, E/A ratio, baPWV, and AIx were measured at baseline, 6 months, and 2 years. Results Baseline characteristics of both groups were similar. The decrease in brachial BP over 2 years was similar in both groups. CBP, LVMI, E/e′ ratio, baPWV, and AIx decreased significantly, and the E/A ratio and e′ velocity increased significantly in both groups. The decreases in CBP (P < 0.001), AIx (P < 0.001), baPWV (P < 0.001), LVMI (P < 0.001), and E/e′ (P = 0.002) as well as the increase in E/A ratio (P = 0.03) over 2 years were significantly greater in the olmesartan/azelnidipine group than in the olmesartan/amlodipine group. Multivariate linear regression analyses showed that the changes in baPWV (β = 0.41, P < 0.001) and CBP (β = 0.47, P = 0.01) were independently associated with the change in LVMI, the change in baPWV (β = 0.25, P < 0.001) was independently associated with the change in E/e′ ratio, and the changes in baPWV (β = 0.21, P = 0.001) and AIx (β = 0.25, P = 0.03) were independently associated with the change in E/A ratio. Conclusion Treatment with olmesartan/azelnidipine for 2 years resulted in greater improvements in CBP, LVMI, and LV diastolic function, and arterial stiffness compared with olmesartan/amlodipine. Improvements in LV diastolic function were associated with improvements in arterial stiffness.


Vascular Health and Risk Management | 2011

Effects of Azelnidipine plus OlmesaRTAn versus amlodipine plus olmesartan on central blood pressure and left ventricular mass index: the AORTA study.

Takeshi Takami; Yoshihiko Saito

Purpose: The aim of this study was to compare the effects of olmesartan combined with either azelnidipine or amlodipine on central blood pressure (CBP) and left ventricular mass index (LVMI) in hypertensive patients. Patient and methods: Patients with brachial systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg received olmesartan monotherapy (20 mg daily) for 12 weeks. The patients were then randomly assigned to fixed-dose add-on therapy with azelnidipine (16 mg daily) or amlodipine (5 mg daily) (25 patients/group) for a further 24 weeks. CBP and LVMI were measured at baseline and at the end of the study. Results: Baseline characteristics were similar in both groups. The decrease in brachial BP was similar in both groups. CBP and LVMI decreased significantly in both groups (both, P < 0.001). However, the decreases in CBP and LVMI were significantly greater with olmesartan/azelnidipine than with olmesartan/amlodipine (CBP, P < 0.001; LVMI, P = 0.002). Conclusions: These findings indicate that olmesartan/azelnidipine had greater effects on CBP and LVMI than did olmesartan/amlodipine, even though the reduction in brachial BP was similar in both groups. These differential effects on CBP and LVMI may have important implications for cardiovascular risk reduction.


Cellular Immunology | 1976

The role of hapten-reactive T lymphocytes in the induction of autoimmunity in mice: I. Establishment of the experimental conditions for the termination of immunological tolerance to human gamma globulin☆

Uki Yamashita; Takeshi Takami; Toshiyuki Hamaoka; Masayasu Kitagawa

Abstract In order to study the role of hapten-reactive helper T cells in the induction of autoimmunity in mice, an attempt was made to establish an experimental model for the development of hapten-reactive helper T cells and the termination of immunological tolerance against heterologous proteins. Spleen cells taken from mice which were immunized with hapten-isologous protein conjugates (PAB-MGG) demonstrated helper activity for the anti-DNP antibody response of DNP-primed B cells responding to DNP and PAB-conjugated protein, but spleen cells from hapten-heterologous protein conjugate (PAB-HGG)-primed mice could not respond to PAB-determinant. Thus, hapten-reactive helper T cells can develop in mice by the immunization with hapten-isologous protein conjugate, but not with hapten-heterologous protein conjugate. However, spleen cells from mice which had been rendered tolerant by treatment with 2.5 or 0.2 mg of DHGG and then immunized with PAB-HGG could demonstrate helper activity responding to PAB-determinant. This helper activity was PAB-specific, because these spleen cells did not demonstrate helper activity if PAB-determinant was omitted in the primary and the secondary antigen. This helper activity was abrogated by the treatment of spleen cells with anti-θ serum and complement. Thus, hapten-reactive helper T cells were successfully induced by the challenge with hapten-heterologous protein conjugate in carrier-protein tolerant mice. When mice were treated with 2.5 or 0.2 mg of DHGG, no anti-HGG antibody response was induced by the challenge with HGG or PAB-HGG. However, the termination of HGG-tolerance was demonstrated only when the mice were preimmunized with PAB-MGG to raise PAB-rcactive helper T cells, treated with 0.2 mg of DHGG, and then challenged with PAB-HGG. This termination of immunological tolerance was not observed when the mice were preimmunized with PAB-BαA to raise PAB-specific B cells and anti-PAB antibody, or when the mice were treated with 2.5 mg of DHGG. Thus, if HGG-specific B cells remain intact in mice such as treated with low dose of DHGG, these B cells can be activated by some bypass mechanisms in the presence of PAB-reactive helper T cells through the PAB-determinant even in the absence of HGG-reactive helper T cells. These data clearly showed the role of hapten-reactive helper T cells in the termination of immunological tolerance and provide experimental supports to the hypothesis on the termination mechanism proposed by Weigle. The cellular mechanism for the development of hapten-reactive helper T cells in tolerant animals and the cellular mechanism of autoantibody production were discussed on the basis of T-B cell collaboration.


Vascular Health and Risk Management | 2012

Major risk factors for the appearance of white-matter lesions on MRI in hypertensive patients with controlled blood pressure

Takeshi Takami; Shigeru Yamano; Sadanori Okada; Mio Sakuma; Takeshi Morimoto; Hiroshi Hashimoto; Satoshi Somekawa; Yoshihiko Saito

Purpose Blood pressure (BP), age, and reduced renal function are major risk factors for white-matter lesions (WMLs) in the general population. However, it remains unclear whether or not the BP itself or other parameters related to the BP are associated with WMLs in hypertensive patients with well-controlled BP. We investigated the relationships of the presence of WMLs with the central systolic BP (cSBP) and estimated glomerular filtration rate (eGFR) in treated hypertensive patients. Method We studied 185 hypertensive patients with median duration of hypertension, 10.0 years, whose BP is controlled to SBP and diastolic BP (DBP) of 139 ± 17 and 79 ± 10 mmHg, respectively. We measured cSBP and brain magnetic resonance imaging (MRI) was examined within 2 weeks after last BP and biological measurements. Results Patients with higher-grade WMLs, as assessed by the presence of Scheltens deep white-matter hyperintensity (SDWMH) in the frontal (grade 0–2 vs 3–6) and parietal areas (grade 0–2 vs 3–6) where small arteries are affected at earlier stage of hypertension, as well as that of Fazekas deep white-matter hyperintensity (FDWMH) (grade 2–3 vs 0–1) and Fazekas periventricular hyperintensity (FPVH) (grade 1–3 vs 0) were older, had higher serum creatinine levels, a longer duration of hypertension, and lower eGFR values. The grade of the WMLs was not associated with either the cSBP or the brachial SBP. In logistic regression analyses after adjustment for age, sex, cSBP, and hypertension duration, showed significant association between eGFR and WMLs. The patients with lower eGFR (<60 mL/minute/1.73 m2) tended to have higher grade WMLs. The odds ratio was 2.87 for FDWMH (P = 0.017), 1.99 for FPVH (P = 0.131), and 2.33 for SDWMH in the parietal area (P = 0.045). Conclusion Presence of WMLs was associated with eGFR, but not with either the brachial SBP or cSBP in hypertensive patients with well-controlled BP.


Hypertension Research | 2009

Evaluation of arterial stiffness in morning hypertension under high-dose valsartan compared to valsartan plus low-dose diuretic

Takeshi Takami

Morning hypertension has been reported to be an important risk factor for cardiovascular events, and arterial stiffness bears a relationship with cardiovascular risk. The aim of this study was to evaluate whether high-dose angiotensin II receptor blocker (ARB) treatment has a more beneficial effect on arterial stiffness than regular-dose ARB plus low-dose diuretic treatment in patients with morning hypertension. Forty-three patients, in whom the home systolic blood pressure (BP) in the morning was higher than 140 mm Hg and in the evening was lower than 135 mm Hg, despite treatment with 80 mg valsartan, were randomly assigned to receive 160 mg valsartan (V group, n=22) or 80 mg valsartan plus low-dose trichlormethiazide (1 mg) (V+D group, n=21) for 6 months. There were no differences in the patient background characteristics between the two groups. There were no significant differences in BP measured at home between the two groups. The brachial–ankle pulse wave velocity (baPWV) at the time of diagnosis of morning hypertension was similar in the two groups; however, after 6 months of treatment, a greater degree of reduction of the baPWV and a greater degree of reduction of BP in the supine position were observed in the V group compared with the V+D group. Thus, though both high-dose valsartan and valsartan plus diuretic reduced the BP to a similar degree in patients with morning hypertension, high-dose valsartan exerted a greater beneficial effect on arterial stiffness than did valsartan plus diuretic.

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Mio Sakuma

Hyogo College of Medicine

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