Hiroyuki Takashima

Hiroyuki Takashima


Research Focus & Metrics

Academic Career Length

11Years (2016-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 March 2020 in Nutrients
Verified
Journal Article
Open access
PDF file
SSSatoshi Shimizu
Satoshi Shimizu
RTRitsukou Tei
Ritsukou Tei
MOMasahiro Okamura
Masahiro Okamura
NTnobuteru takao
nobuteru takao
YNYoshihiro Nakamura
Yoshihiro Nakamura
MAMasanori Abe
Masanori Abe
Background: It is known that patients on hemodialysis (HD) are prone to developing zinc deficiency due to removal of zinc by HD, inadequate dietary intake, and reduced gastrointestinal zinc absorption. However, the prevalence of zinc deficiency in patients on peritoneal dialysis (PD) has not been well established. Methods: Serum zinc levels were compared between 47 patients on PD and 47 patients on HD matched for age, sex, and duration of dialysis. A serum zinc level < 60 μg/dL was defined as clinical zinc deficiency and a level of 60–80 μg/dL as subclinical zinc deficiency. The prevalence of zinc deficiency and associated clinical factors were determined in both groups. Results: Clinical zinc deficiency was found in 59.6% of the PD group and 70.2% of the HD group (p = 0.391). Subclinical zinc deficiency was found in 40.4% of the PD group and 29.8% of the HD group. Age, body mass index, and serum albumin level were identified as independent predictors of zinc deficiency in the PD group by multivariate analysis. Conclusions: A higher prevalence of clinical and subclinical zinc deficiency was found in patients on PD. The rates were comparable between patients on PD and those on HD after adjustment for confounding factors.

25 April 2016 in Diabetes Research and Clinical Practice
Verified
Journal Article
Open access
PDF file
MAMasanori Abe
Masanori Abe
HTHiguchi Terumi
Higuchi Terumi
MMMasari Moriuchi
Masari Moriuchi
MOMasahiro Okamura
Masahiro Okamura
RTRitsukou Tei
Ritsukou Tei
KOKazuyoshi Okada
Kazuyoshi Okada
Saxagliptin is a dipeptidyl peptidase-4 inhibitor that was approved in Japan for the treatment of type 2 diabetes in 2013. We examined its efficacy and safety in Japanese hemodialysis patients with diabetic nephropathy. In this prospective, open-label, parallel-group study, Japanese hemodialysis patients were randomized to receive either oral saxagliptin (2.5mg/day) or usual care (control group) for 24weeks. Before randomization, patients received fixed doses of conventional antidiabetic drugs (oral drugs and/or insulin) for 8weeks; these drugs were continued during the study. Endpoints included changes in glycated albumin (GA), hemoglobin A1c (HbA1c), postprandial plasma glucose (PPG), and adverse events. Both groups included 41 patients. Mean GA, HbA1c, and PPG decreased significantly in the saxagliptin group (-3.4%, -0.6% [-7mmol/mol], and -38.3mg/dL, respectively; all P<0.0001) but not in the control group (0%, -0.1% [-1mmol/mol], and -3.7mg/dL, respectively) (P<0.0001, P<0.001, and P<0.0001, respectively). In saxagliptin-treated patients, the reduction in GA was significantly greater when saxagliptin was administered as monotherapy than in combination therapy (-4.2% vs. -3.0%, P=0.012) despite similar baseline values (24.5% vs. 23.3%). Reductions in GA, HbA1c, and PPG were greater in patients whose baseline values exceeded the median (23.8% for GA, 6.6% for HbA1c, and 180mg/dL for PPG). There were no adverse events associated with saxagliptin. Saxagliptin (2.5mg/day) was effective and well tolerated when used as monotherapy or combined with other antidiabetic drugs in Japanese hemodialysis patients with type 2 diabetes. UMIN000018445.

4 November 2019 in Nutrients
Verified
Journal Article
Open access
PDF file
SSSatoshi Shimizu
Satoshi Shimizu
HTHiroyuki Takashima
Hiroyuki Takashima
RTRitsukou Tei
Ritsukou Tei
TFTetsuya Furukawa
Tetsuya Furukawa
MOMakiyo Okamura
Makiyo Okamura
MAMasanori Abe
Masanori Abe
Background: Carnitine deficiency is common in patients on dialysis. Serum free carnitine concentration is significantly lower in patients on hemodialysis (HD) than in healthy individuals. However, there are few reports on serum free carnitine concentration in patients on peritoneal dialysis (PD). Methods: We examined serum concentrations of total, free, and acylcarnitine and the acylcarnitine/free carnitine ratio in 34 PD and 34 age-, sex-, and dialysis duration-matched HD patients. We investigated the prevalence of carnitine deficiency and clinical factors associated with carnitine deficiency in the PD group. Results: Prevalence of carnitine deficiency was 8.8% in the PD group and 17.7% in the HD group (p = 0.283). High risk of carnitine deficiency was found in 73.5% of the PD group and 76.4% of the HD group (p = 0.604). Carnitine insufficiency was found in 82.3% of the PD group and 88.2% of HD group (p = 0.733). Multivariate analysis revealed that duration of dialysis and age were independent predictors of serum free carnitine level in the PD group. Conclusions: The prevalence of carnitine deficiency, high risk of carnitine deficiency, and carnitine insufficiency in PD patients was 8.8%, 73.5%, and 82.3%, respectively. These rates were comparable to those in patients on HD.