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Dive into the research topics where Takahiro Aoki is active.

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Featured researches published by Takahiro Aoki.


PLOS ONE | 2011

Impact of small body weight on tenofovir-associated renal dysfunction in HIV-infected patients: a retrospective cohort study of Japanese patients.

Takeshi Nishijima; Hirokazu Komatsu; Hiroyuki Gatanaga; Takahiro Aoki; Koji Watanabe; Ei Kinai; Haruhito Honda; Junko Tanuma; Hirohisa Yazaki; Kunihisa Tsukada; Miwako Honda; Katsuji Teruya; Yoshimi Kikuchi; Shinichi Oka

Background Treatment with tenofovir is sometimes associated with renal dysfunction. Limited information is available on this side effect in patients with small body weight, although the use of tenofovir will spread rapidly in Asia and Africa, where patients are likely to be of smaller body weight. Methods In a single-center cohort, Japanese patients with HIV infection who started tenofovir-containing antiretroviral therapy were retrospectively analyzed. The incidence of tenofovir-associated renal dysfunction, defined as more than 25% decrement of estimated glomerular filtration rate (eGFR) from the baseline, was determined. The effects of small body weight and body mass index (BMI) on tenofovir-associated renal dysfunction, respectively, were estimated in univariate and multivariate Cox hazards models as the primary exposure. Other possible risk factors were evaluated by univariate analysis and those found significant were entered into the multivariate analysis. Results The median weight of 495 patients was 63 kg. Tenofovir-related renal dysfunction occurred in 97 (19.6%) patients (incidence: 10.5 per 100 person-years). Univariate analysis showed that the incidence of tenofovir-related renal dysfunction was significantly associated with smaller body weight and BMI, respectively (per 5 kg decrement, HR = 1.23; 95% CI, 1.10–1.37; p<0.001)(per 1 kg/m2 decrement, HR = 1.14; 95% CI, 1.05–1.23; p = 0.001). Old age, high baseline eGFR, low serum creatinine, low CD4 count, high HIV viral load, concurrent nephrotoxic drugs, hepatitis C infection, and current smoking were also associated with tenofovir-related renal dysfunction. Multivariate analysis identified small body weight as a significant risk (adjusted HR = 1.13; 95% CI, 1.01–1.27; p = 0.039), while small BMI had marginal significance (adjusted HR = 1.07; 95% CI 1.00–1.16; p = 0.058). Conclusion The incidence of tenofovir-associated renal dysfunction in Japanese patients was high. Small body weight was identified as an independent risk factor for tenofovir-associated renal dysfunction. Close monitoring of renal function is advocated for patients with small body weight treated with tenofovir.


PLOS ONE | 2012

Renal function declines more in tenofovir- than abacavir-based antiretroviral therapy in low-body weight treatment-naïve patients with HIV infection.

Takeshi Nishijima; Hiroyuki Gatanaga; Hirokazu Komatsu; Kunihisa Tsukada; Takuro Shimbo; Takahiro Aoki; Koji Watanabe; Ei Kinai; Haruhito Honda; Junko Tanuma; Hirohisa Yazaki; Miwako Honda; Katsuji Teruya; Yoshimi Kikuchi; Shinichi Oka

Objective To compare the rate of decline of renal function in tenofovir- and abacavir-based antiretroviral therapy (ART) in low-body weight treatment-naïve patients with HIV infection. Design We conducted a single-center retrospective cohort study of 503 Japanese patients who commenced on either tenofovir- or abacavir-based initial ART. Methods The incidence of renal dysfunction, defined as more than 25% fall in estimated glomerular filtration rate (eGFR) from the baseline, was determined in each group. The effect of tenofovir on renal dysfunction was estimated by univariate and multivariate Cox hazards models as the primary exposure. Changes in eGFR until 96 weeks were estimated in both groups with a repeated measures mixed model. Results The median body weight of the cohort was 64 kg. The estimated incidence of renal dysfunction in the tenofovir and the abacavir arm was 9.84 per 100 and 4.55 per 100 person-years, respectively. Tenofovir was significantly associated with renal dysfunction by univariate and multivariate analysis (HR = 1.747; 95% CI, 1.152–2.648; p = 0.009) (adjusted HR = 2.080; 95% CI, 1.339–3.232; p<0.001). In subgroup analysis of the patients stratified by intertertile baseline body weight, the effect of tenofovir on renal dysfunction was more evident in patients with lower baseline body weight by multivariate analysis (≤60 kg: adjusted HR = 2.771; 95%CI, 1.494–5.139; p = 0.001) (61–68 kg: adjusted HR = 1.908; 95%CI, 0.764–4.768; p = 0.167) (>68 kg: adjusted HR = 0.997; 95%CI, 0.318–3.121; p = 0.995). The fall in eGFR was significantly greater in the tenofovir arm than the abacavir arm after starting ART (p = 0.003). Conclusion The incidence of renal dysfunction in low body weight patients treated with tenofovir was twice as high as those treated with abacavir. Close monitoring of renal function is recommended for patients with small body weight especially those with baseline body weight <60 kg treated with tenofovir.


AIDS | 2014

Long-term exposure to tenofovir continuously decrease renal function in HIV-1-infected patients with low body weight: results from 10 years of follow-up.

Takeshi Nishijima; Yohei Kawasaki; Daisuke Mizushima; Takahiro Aoki; Koji Watanabe; Ei Kinai; Haruhito Honda; Hirohisa Yazaki; Junko Tanuma; Kunihisa Tsukada; Katsuji Teruya; Yoshimi Kikuchi; Hiroyuki Gatanaga; Shinichi Oka

Objectives:To investigate the effect of long-term tenofovir disoproxil fumarate (TDF) use on renal function, especially in patients with low body weight who are vulnerable to TDF nephrotoxicity. Design:A single-center, observational study in Tokyo, Japan. Methods:We performed a 10 years cohort study of 792 HIV-1-infected patients. The effect of long-term TDF use on estimated glomerular filtration rate (eGFR) was investigated on treatment-naive patients who started TDF-containing antiretroviral therapy (n = 422) and those who started abacavir-containing antiretroviral therapy as control (n = 370). Three renal endpoints were examined by the logistic regression model: decrement in eGFR of higher than 10 ml/min per 1.73 m2 relative to the baseline, more than 25% decrement in eGFR, and eGFR lower than 60 ml/min per 1.73 m2 at least 3 months apart. The loss in eGFR was estimated using linear mixed models for repeated measures. Results:The median weight at baseline was 63 kg. TDF use increased the risk of all three renal outcomes compared with the control group: higher than 10 ml/min per 1.73 m2 decrement in eGFR [adjusted odds ratio (OR) = 2.1, 95% confidence interval (CI) 1.45–3.14, P < 0.001], more than 25% decrement (adjusted OR = 2.1, 95% CI 1.50–2.90, P < 0.001), and eGFR lower than 60 ml/min per 1.73 m2 at least 3 months apart (adjusted OR = 3.9, 95% CI 1.62–9.36, P = 0.002). The cumulative mean loss relative to the control after 1, 2, 3, 4, and 5 years of TDF exposure was −3.8, −3.6, −5.5, −6.6, and −10.3 ml/min per 1.73 m2, respectively, indicating that the loss in eGFR increased over time (P < 0.001). Conclusion:In this cohort of patients with low body weight, TDF exposure increased the risk of renal dysfunction. Furthermore, the loss in eGFR relative to the control increased continuously up to 5 years.


The Journal of Infectious Diseases | 2014

Clinical Significance of High Anti-Entamoeba histolytica Antibody Titer in Asymptomatic HIV-1-infected Individuals

Koji Watanabe; Takahiro Aoki; Naoyoshi Nagata; Junko Tanuma; Yoshimi Kikuchi; Shinichi Oka; Hiroyuki Gatanaga

BACKGROUND Anti-Entamoeba histolytica antibody (anti- E. histolytica) is widely used in seroprevalence studies though its clinical significance has not been assessed previously. METHODS Anti-E. histolytica titer was measured at first visit to our clinic (baseline) in 1303 patients infected with human immunodeficiency virus type 1 (HIV-1). The time to diagnosis of invasive amebiasis was assessed by Kaplan-Meier method and risk factors for the development of invasive amebiasis were assessed by Cox proportional-hazards regression analysis. For patients who developed invasive amebiasis, anti-E. histolytica titers at onset were compared with those at baseline and after treatment. RESULTS The anti-E. histolytica seroprevalence in the study population was 21.3% (277/1303). Eighteen patients developed invasive amebiasis during the treatment-free period among 1207 patients who had no history of previous treatment with nitroimidazole. Patients with high anti-E. histolytica titer at baseline developed invasive amebiasis more frequently than those with low anti-E. histolytica titer. Most cases of invasive amebiasis who had high anti-E. histolytica titer at baseline developed within 1 year. High anti-E. histolytica titer was the only independent predictor of future invasive amebiasis. Anti-E. histolytica titer was elevated at the onset of invasive amebiasis in patients with low anti-E. histolytica titer at baseline. CONCLUSIONS Asymptomatic HIV-1-infected individuals with high anti-E. histolytica titer are at risk of invasive amebiasis probably due to exacerbation of subclinical amebiasis.


Clinical Infectious Diseases | 2015

High-Dose Oral Amoxicillin Plus Probenecid Is Highly Effective for Syphilis in Patients With HIV Infection

Ryutaro Tanizaki; Takeshi Nishijima; Takahiro Aoki; Katsuji Teruya; Yoshimi Kikuchi; Shinichi Oka; Hiroyuki Gatanaga

BACKGROUND Intramuscular benzathine penicillin G (BPG) is widely used for the treatment of syphilis. However, BPG is not available in some countries. This study examined the effectiveness and safety of high-dose oral amoxicillin plus probenecid for the treatment of syphilis in patients with human immunodeficiency virus type 1 (HIV-1). METHODS This retrospective observational study included 286 HIV-infected male patients with syphilis (median age, 36 years; median CD4 count, 389 cells/µL) who were treated with oral amoxicillin 3 g plus probenecid. Syphilis was diagnosed by both serum rapid plasma reagin (RPR) titers ≥8 and positive Treponema pallidum hemagglutination test. Patients with neurosyphilis diagnosed by cerebrospinal fluid examination were excluded. Successful treatment was defined as a at least 4-fold decrement in RPR titer. RESULTS The overall treatment efficacy was 95.5% (95% confidence interval [CI], 92.4%-97.7%; 273/286 patients), and efficacy for primary, secondary, early latent, late latent, and unknown duration syphilis was 93.8% (95% CI, 68.1%-99.8%; 15/16), 97.3% (95% CI, 92.9%-99.2%; 142/146), 100% (95% CI, 90.5%-100%; 37/37), 85.7% (95% CI, 58.6%-96.4%; 18/21), and 92.4% (95% CI, 81.9%-97.3%; 61/66), respectively. Treatment duration was mostly 14-16 days (49.7%) or 28-30 days (34.3%), with efficacy of 94.4% (134/142) and 95.9% (94/98), respectively; 96.3% of successfully treated patients achieved a ≥4-fold decrement in RPR titer within 12 months. Adverse events were noted in 28 (9.8%) patients, and 25 of these (89.3%) were successfully treated. Only 6% of patients underwent lumbar puncture. CONCLUSIONS The combination of oral amoxicillin 3 g plus probenecid was highly effective and tolerable for the treatment of syphilis in patients with HIV-1 infection.


International Journal of Medical Sciences | 2013

Potential function of granulysin, other related effector molecules and lymphocyte subsets in patients with TB and HIV/TB coinfection.

Nada Pitabut; Shinsaku Sakurada; Takahiro Tanaka; Chutharut Ridruechai; Junko Tanuma; Takahiro Aoki; Pacharee Kantipong; Surachai Piyaworawong; Nobuyuki Kobayashi; Panadda Dhepakson; Hideki Yanai; Norio Yamada; Shinichi Oka; Masaji Okada; Srisin Khusmith; Naoto Keicho

Background: Host effector mechanism against Mycobacterium tuberculosis (Mtb) infection is dependent on innate immune response by macrophages and neutrophils and the alterations in balanced adaptive immunity. Coordinated release of cytolytic effector molecules from NK cells and effector T cells and the subsequent granule-associated killing of infected cells have been documented; however, their role in clinical tuberculosis (TB) is still controversy. Objective: To investigate whether circulating granulysin and other effector molecules are associated with the number of NK cells, iNKT cells, Vγ9+Vδ2+ T cells, CD4+ T cells and CD8+ T cells, and such association influences the clinical outcome of the disease in patients with pulmonary TB and HIV/TB coinfection. Methods: Circulating granulysin, perforin, granzyme-B and IFN-γ levels were determined by ELISA. The isoforms of granulysin were analyzed by Western blot analysis. The effector cells were analyzed by flow cytometry. Results: Circulating granulysin and perforin levels in TB patients were lower than healthy controls, whereas the granulysin levels in HIV/TB coinfection were much higher than in any other groups, TB and HIV with or without receiving HAART, which corresponded to the number of CD8+ T cells which kept high, but not with NK cells and other possible cellular sources of granulysin. In addition, the 17kDa, 15kDa and 9kDa isoforms of granulysin were recognized in plasma of HIV/TB coinfection. Increased granulysin and decreased IFN-γ levels in HIV/TB coinfection and TB after completion of anti-TB therapy were observed. Conclusion: The results suggested that the alteration of circulating granulysin has potential function in host immune response against TB and HIV/TB coinfection. This is the first demonstration so far of granulysin in HIV/TB coinfection.


PLOS ONE | 2013

Pharmacokinetics of Rifabutin in Japanese HIV-Infected Patients with or without Antiretroviral Therapy

Junko Tanuma; Kazumi Sano; Katsuji Teruya; Koji Watanabe; Takahiro Aoki; Haruhito Honda; Hirohisa Yazaki; Kunihisa Tsukada; Hiroyuki Gatanaga; Yoshimi Kikuchi; Shinichi Oka

Objective Based on drug-drug interaction, dose reduction of rifabutin is recommended when co-administered with HIV protease inhibitors for human immunodeficiency virus (HIV)-associated mycobacterial infection. The aim of this study was to compare the pharmacokinetics of rifabutin administered at 300 mg/day alone to that at 150 mg every other day combined with lopinavir-ritonavir in Japanese patients with HIV/mycobacterium co-infection. Methods Plasma concentrations of rifabutin and its biologically active metabolite, 25-O-desacetyl rifabutin were measured in 16 cases with HIV-mycobacterial coinfection. Nine were treated with 300 mg/day rifabutin and 7 with 150 mg rifabutin every other day combined with lopinavir-ritonavir antiretroviral therapy (ART). Samples were collected at a median of 15 days (range, 5–63) of rifabutin use. Results The mean Cmax and AUC0–24 of rifabutin in patients on rifabutin 150 mg every other day were 36% and 26% lower than on 300 mg/day rifabutin, while the mean Cmax and AUC0–24 of 25–O-desacetyl rifabutin were 186% and 152% higher, respectively. The plasma concentrations of rifabutin plus its metabolite were similar between the groups within the first 24 hours, but it remained low during subsequent 24 to 48 hours under rifabutin 150 mg alternate day dosing. Conclusion Rifabutin dose of 150 mg every other day combined with lopinavir-ritonavir seems to be associated with lower exposure to rifabutin and its metabolite compared with rifabutin 300 mg/day alone in Japanese patients. Further studies are needed to establish the optimal rifabutin dose during ART. The results highlight the importance of monitoring rifabutin plasma concentration during ART. Trial registration UMIN-CTR (https://upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function=search&action=input&language=E) UMIN000001102


PLOS ONE | 2016

High Mortality of Disseminated Non-Tuberculous Mycobacterial Infection in HIV-Infected Patients in the Antiretroviral Therapy Era

Tetsuro Kobayashi; Takeshi Nishijima; Katsuji Teruya; Takahiro Aoki; Yoshimi Kikuchi; Shinichi Oka; Hiroyuki Gatanaga

Background Little information is available on the mortality and risk factors associated with death in disseminated non-tuberculous mycobacterial infection (dNTM) in HIV-infected patients in the ART-era. Methods In a single-center study, HIV-infected dNTM with positive NTM culture from sterile sites between 2000 and 2013 were analysed. The clinical characteristics at commencement of anti-mycobacterial treatment (baseline) were compared between those who survived and died. Results Twenty-four patients were analyzed. [The median CD4 27/μL (range 2–185)]. Mycobacterium avium and M. intracellulare accounted for 20 (83%) and 3 (13%) of isolated NTM. NTM bacteremia was diagnosed in 15 (63%) patients. Seven (29%) patients died, and NTM bacteremia was significantly associated with mortality (p = 0.022). The baseline CD4 count was significantly lower in the non-survivors than the survivors (median 7/μL versus 49, p = 0.034). Concomitant AIDS-defining diseases or malignancies were not associated with mortality. Immune-reconstitution syndrome (IRS) occurred to 19 (79%) patients (8 paradoxical and 11 unmasking), and prognosis tended to be better in unmasking-IRS than the other patients (n = 13) (p = 0.078). Patients with paradoxical-IRS had marginally lower CD4 count and higher frequency of bacteremia than those with unmasking-IRS (p = 0.051, and 0.059). Treatment with systemic corticosteroids was applied in 63% and 55% of patients with paradoxical and unmasking-IRS, respectively. Conclusion dNTM in HIV-infected patients resulted in high mortality even in the ART-era. NTM bacteremia and low CD4 count were risk factors for death, whereas patients presented with unmasking-IRS had marginally better prognosis. IRS occurred in 79% of the patients, suggesting difficulty in the management of dNTM.


PLOS ONE | 2015

A 21-Day of Adjunctive Corticosteroid Use May Not Be Necessary for HIV-1-Infected Pneumocystis Pneumonia with Moderate and Severe Disease

Satoshi Shibata; Takeshi Nishijima; Takahiro Aoki; Yoshinari Tanabe; Katsuji Teruya; Yoshimi Kikuchi; Toshiaki Kikuchi; Shinichi Oka; Hiroyuki Gatanaga

Background The current guidelines recommend 21-day adjunctive corticosteroid therapy for HIV-1-infected pneumocystis pneumonia patients (HIV-PCP) with moderate-to-severe disease. Whether shorter adjunctive corticosteroid therapy is feasible in such patients is unknown. Methods We conducted a retrospective study to elucidate the proportion of patients with moderate and severe HIV-PCP who required adjunctive corticosteroid therapy for 21 days. The enrollment criteria included HIV-PCP that fulfilled the current criteria for 21-day corticosteroid therapy; PaO2 on room air of <70mmHg or A-aDO2 ≥35 mmHg. Results The median duration of corticosteroid therapy in the 73 study patients was 13 days (IQR 9–21). Adjunctive corticosteroid therapy was effective and discontinued within 10 and 14 days in 30% and 60% of the patients, respectively. Only 9% of the patients with moderate HIV-PCP (n = 22, A-aDO2 35–45 mmHg) received steroids for >14 days, whereas 35% of the patients with severe HIV-PCP (n = 51, A-aDO2 ≥45 mmHg) required corticosteroid therapy for ≥21 days. Four (13%) of the severe cases died, whereas no patient with moderate disease died. Among patients with severe HIV-PCP, discontinuation of corticosteroid therapy within 14 days correlated significantly with higher baseline CD4 (p = 0.049). Conclusion Shorter adjunctive corticosteroid therapy was clinically effective and adjunctive corticosteroid could be discontinued within 14 days in 60% of moderate-to-severe HIV-PCP and 90% of moderate cases.


PLOS ONE | 2017

Interferon-free therapy with direct acting antivirals for HCV/HIV-1 co-infected Japanese patients with inherited bleeding disorders

Haruka Uemura; Kunihisa Tsukada; Daisuke Mizushima; Takahiro Aoki; Koji Watanabe; Ei Kinai; Katsuji Teruya; Hiroyuki Gatanaga; Yoshimi Kikuchi; Masaya Sugiyama; Masashi Mizokami; Shinichi Oka

Introduction Almost 30 years ago, about 30% of Japanese hemophiliacs became infected with HIV-1 and hepatitis C virus (HCV) after receiving contaminated blood products. While several studies have reported the high efficacy and safety of direct acting antivirals (DAA) in HIV-1 co-infected patients, such data are limited in hemophiliacs. Methods We conducted a single-center, open-label study involving 27 Japanese patients (median age; 45 years) with inherited bleeding disorders who were co-infected with HCV/HIV-1. Patients with HCV genotype 1 (GT1) and GT4 received ledipasvir (90 mg) plus sofosbuvir (400 mg), those with HCV GT2 received sofosbuvir plus weight-based ribavirin, and those with HCV GT3 received daclatasvir (60 mg) plus sofosbuvir. Treatment was continued for 12 weeks in all patients. The primary endpoints were rate of sustained virologic response at 12 weeks after end of therapy (SVR12) and occurrence of adverse events during DAA therapy. Results Eighteen (67%) patients had had received interferon-based therapy, and 11 (41%) had compensated cirrhosis. HCV genotypes were GT1a 4 (15%), GT1b 16 (59%), GT1 undetermined 2 (7%), GT2a 1 (4%), GT3a 3 (11%) and GT4a 1 (4%). All patients were on combination antiretroviral therapy (cART) and had undetectable HIV-1 viral load (<20 copies/μL) at baseline. All patients achieved SVR12. Serious adverse events were observed in 3 patients: arteritis of the leg, which resolved after completion of DAA therapy, asymptomatic QT prolongation and gastrointestinal hemorrhage. cART failure was noted in one patient due to emergence of raltegravir resistance during ledipasvir/sofosbuvir treatment. Although α-fetoprotein, Mac-2 binding protein glycosylation isomer (M2BPGi), and Fibro Scan (FS) scores decreased in most patients during DAA therapy, M2BPGi (>2.0 cutoff index) and FS scores (>15.0 kPa) were still high in 6 patients at week 36. Conclusions DAA therapy is effective in all patients. However, adverse events and efficacy of cART should be monitored closely.

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Takeshi Nishijima

Tokyo Metropolitan University

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