Publications by authors named "Hidehiko Suzuki"

37 Publications

Mucosal vaccination using claudin-4-targeting.

Biomaterials 2010 Jul;31(20):5463-71

Laboratory of Bio-Functional Molecular Chemistry, Graduate School of Pharmaceutical Sciences, Osaka University, Suita, Osaka 565-0871, Japan.

Mucosa-associated lymphoid tissue (MALT) plays pivotal roles in mucosal immune responses. Efficient delivery of antigens to MALT is a critical issue for the development of mucosal vaccines. Although claudin-4 is preferentially expressed in MALT in the gut, a claudin-4-targeting approach for mucosal vaccination has never been developed. In the present study, we found that claudin-4 is expressed in nasal MALT, and we prepared a fusion protein of ovalbumin (OVA) as a model antigen with a claudin-4-binder, the C-terminal fragment of Clostridium perfringens enterotoxin (C-CPE) (OVA-C-CPE). Nasal immunization with OVA-C-CPE, but not a mixture of OVA and C-CPE, induced the production of OVA-specific serum IgG and nasal, vaginal and fecal IgA. Deletion of the claudin-4-binding region in OVA-C-CPE attenuated the induction of the immune responses. OVA-C-CPE immunization activated both Th1 and Th2 responses, and nasal immunization with OVA-C-CPE showed anti-tumor activity in mice inoculated with OVA-expressing thymoma cells. These results indicate that the claudin-4-targeting may be a potent strategy for nasal vaccination.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.biomaterials.2010.03.047DOI Listing
July 2010

Fast spectrometer for ground-based observations of OH rotational temperature.

Appl Opt 2009 Feb;48(6):1119-27

National Institute of Polar Research, Tokyo, Japan.

A sensitive spectrometer has been developed for observing the hydroxyl airglow in the polar region. This spectrometer is designed to acquire spectra of the Meinel OH 8-4 band, which has the advantage of being relatively free of contamination from auroral emissions. The spectrometer consists of a fast optical system, a transmission plane grating, and a cooled CCD image sensor. The spectrometer can acquire spectra between 900 and 987 nm, from which the OH rotational temperature can be derived with an accuracy of ± 1.9 to 2.5 K for a 1 min? exposure. The spectrometer specifications and initial measurement results for the OH rotational temperature and intensity at Syowa Station (69.0 °S, 39.6 °E) in Antarctica are presented.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1364/ao.48.001119DOI Listing
February 2009

Factors responsible for age-related elevation in fasting plasma glucose: a cross-sectional study in Japanese men.

Metabolism 2008 Feb;57(2):299-303

Department of Diabetes and Clinical Nutrition, Graduate School of Medicine, Kyoto University, Kyoto 606-8507, Japan.

To evaluate the factors associated with age-related increase in fasting plasma glucose (FPG) in Japanese men with normal fasting glucose, we measured FPG, fasting immunoreactive insulin, glycated hemoglobin, total cholesterol, triglyceride, and high-density lipoprotein cholesterol levels in health check examinees. Subjects with FPG less than 6.1 mmol/L together with glycated hemoglobin less than 5.6% were enrolled in the study. The homeostasis model assessment of insulin resistance (HOMA-IR) and HOMA-beta were used as the indices of insulin sensitivity and insulin secretion, respectively. Fasting plasma glucose increased significantly with age (r = 0.30, P < .0001), and HOMA-beta decreased significantly with age (r = 0.24, P < .0001). The HOMA-IR had no significant relation with age (r = 0.06, not significant), whereas body mass index and serum triglyceride were associated with HOMA-IR (r = 0.49, P < .0001 and r = 0.33, P < .0001, respectively). Thus, in Japanese male subjects with normal fasting glucose, it is suggested that the FPG increment with age is associated with decreased beta-cell function rather than with insulin resistance. Further analyses were performed by comparing 3 groups: low FPG (FPG <5.0 mmol/L), high FPG (5.0 < or = FPG < 5.6 mmol/L), and mild impairment of fasting glycemia (mild IFG) (5.6 < or = FPG < 6.1 mmol/L). The insulin levels in mild IFG and high FPG were significantly higher than in low FPG (P < .001), but those in mild IFG were similar to those in high FPG. Analysis of the 3 subgroups revealed that, whereas insulin sensitivity was impaired more in high FPG, there was little compensatory increase in insulin in mild IFG, suggesting that beta-cell function is already deteriorated when the FPG level is greater than 5.6 mmol/L.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.metabol.2007.10.002DOI Listing
February 2008

MRI study of bioabsorbable poly-L-lactic acid devices used for fixation of fracture and osteotomies.

J Orthop Sci 2006 Mar;11(2):154-8

Department of Orthopaedic Surgery, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan.

Background: The overall clinical results of bioabsorbable fixation devices made of poly-L-lactic acid (PLLA) used for fixation of fractures, bone grafting, and osteotomies have been favorable. However, clinical studies demonstrated no sign of normal bony architecture restored after surgery, although implant channels had been filled with fibrous tissue. The purpose of the present retrospective study was to examine the extent of structural changes in PLLA devices (PLLA-Ds) for fixation of rotational acetabular osteotomies and displaced malleolar ankle fractures using magnetic resonance imaging (MRI).

Methods: Altogether, 14 patients with osteoarthritis of hip joints and 15 with displaced malleolar ankle fractures were operated on using PLLA-D (NEOFIX). Of these patients, 22 were finally enrolled in the study, and the period from operation to the time of the study ranged from 17 to 78 months. The postoperative radiographic findings were evaluated for union, and changes around the implant holes were classified as sclerosis, resorption, or no change. MRI was carried out to estimate changes in the PLLA-Ds.

Results: Bone union was obtained in all cases; clinical complications such as infection, joint effusion, soft tissue irritation due to PLLA-D deviation, and motion pain in the joints were not observed. The MRI study suggested that water content in PLLA-D increased mainly due to biodegradation and that implants were not replaced by bony tissue.

Conclusions: The PLLA-Ds were degraded but were not replaced by bony tissue during the observation period. Considering these findings and the assumption that in bony tissues mechanical strength of PLLA-D decreases with time, attention should be paid to mechanical insufficiency, which may occur when the cross-sectional area of a PLLA-D extends beyond the cross-sectional area of the osteosynthesis site.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s00776-005-0989-2DOI Listing
March 2006

Effects of thorough mastication on postprandial plasma glucose concentrations in nonobese Japanese subjects.

Metabolism 2005 Dec;54(12):1593-9

Department of General Medicine and Clinical Epidemiology, Kyoto University Graduate School of Medicine, Kyoto 606-8507, Japan.

Thorough mastication has the potential to affect postprandial plasma glucose concentrations by improving digestibility and absorption of nutrients. To evaluate the effects of mastication on postprandial plasma glucose concentration, we compared usual and thorough mastication in subjects with normal glucose tolerance (NGT group, n = 16) and subjects predisposed to type 2 diabetes (first-degree relatives of type 2 diabetic patients, subjects with impaired glucose tolerance, and type 2 diabetic patients) (predisposed group, n = 10) in a crossover trial of 52 test meals. Plasma glucose and serum insulin concentrations were measured for 3 hours postprandially, and the insulinogenic index (the ratio of incremental serum insulin to plasma glucose concentration during the first 30 minutes after meal) was calculated. In the NGT group, thorough mastication reduced the postprandial plasma glucose concentration at 90 minutes (5.8 +/- 0.3 vs 6.5 +/- 0.4 mmol/L, P < .05) and 120 minutes (5.4 +/- 0.2 vs 6.3 +/- 0.4 mmol/L, P < .05) and the area under the curve (AUC) from -15 to 180 minutes (19.1 +/- 0.6 vs 20.6 +/- 0.8 [mmol . L]/h, P < .05) without an increase in the AUC for insulin. In the predisposed group, thorough mastication significantly augmented plasma glucose and serum insulin concentrations and the AUCs compared with usual mastication. Thorough mastication elicited a significantly higher insulinogenic index than usual mastication in the NGT group (205.0 +/- 27.6 vs 145.6 +/- 17.7 pmol/mmol, P < .05), whereas the predisposed group showed significantly less early-phase insulin secretion than the NGT group. In the NGT group the postprandial plasma glucose concentration upon thorough mastication of meal was significantly lower, most probably because of the potentiation of early-phase insulin secretion. In the subjects predisposed to type 2 diabetes, thorough mastication did not potentiate early-phase insulin secretion and elicited a higher postprandial plasma glucose concentration.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.metabol.2005.06.006DOI Listing
December 2005

Study design, statistical method, and level of evidence in Japanese and American clinical journals.

J Epidemiol 2002 May;12(3):266-70

Department of General Medicine and Clinical Epidemiology, Kyoto University Graduate School of Medicine, Kyoto University Hospital, Japan.

Clinical articles published in Japanese journals are said to be characterized by poor study design, less sophisticated statistics, and producing few high-grade clinical evidences. Two American and two Japanese medical journals, published in 1990, 1993, 1996, and 1999 were compared to find out the differences regarding study design, statistical methods, and level of clinical evidence of original articles and synthetic studies. There were 1689 original articles in American and 308 in Japanese joumals. Regarding study design, American articles contributed much more to randomized controlled trials/controlled trials/clinical trials (27.9% vs. 14.3%, p=0.001), cohort studies (21.6% vs. 6.2%, p=0.001), and case-control studies (6.5% vs.0.3 %, p=0.000). Among original articles in American and Japanese journals, mean number of statistical methods used were 2.4 and 1.7 per article (p=0.000), respectively. Articles providing high grade clinical evidence (grade Ia, Ib & IIa) were much greater in proportion in American journals than Japanese journals (31.1% vs. 12.7%, p=0.001). The overall picture of Japanese medical articles seems to be improving recently, at least in terms of statistical methods toward more diversified and sophisticated way of use, compared to the previous data.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.2188/jea.12.266DOI Listing
May 2002

Suppressive effect of pulmonary hypertension and leukocyte activation by inhaled prostaglandin E1 in rats with monocrotaline-induced pulmonary hypertension.

Exp Lung Res 2002 Jun;28(4):265-73

Department of Cardiology and Pneumology, Dokkyo University School of Medicine, Tochigi Prefecture, Japan.

The effect of long-term prostaglandin E(1) (PGE(1)) aerosol was investigated in rats with chronic pulmonary hypertension induced by monocrotaline (MCT). Six-week-old Sprague-Dawley rats were separated into groups of 6 and administered 1 mL of saline (group A) or 60 mg / kg of MCT. The MCT-treated mice were then administered either nothing (group B) or 5 mL of PGE(1) (4 microg/mL) via a nebulizer every day for 1 week (group C), 2 weeks (group D), 3 weeks (group E), or 4 weeks (group F) after MCT injection. The pulmonary artery medial wall thickness was measured and the weight ratio of the right ventricle to the intraventricular septum plus the left ventricle (RV ratio) was determined 1 month after saline or MCT injection. Leukocytes positive for the activation markers CD18, CD49d, CD62L were determined in each group every week for 1 month. The pulmonary artery medial wall thickness and RV ratio gradually decreased in proportion to the duration of PGE(1) inhalation. In groups E and F, the level of CD62L-positive leukocytes gradually decreased after MCT injection in proportion to the duration of PGE(1) inhalation. We conclude that long-term inhalation of PGE(1) is very useful therapy in chronic pulmonary hypertension and that the antileukocyte effect of PGE(1) is associated with the suppression of CD62L-positive leukocytes at an early stage of progression.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1080/01902140252964357DOI Listing
June 2002
-->