Biomedical subjects

K Hanai

Publications and source records attributed to K Hanai.

At least 19 recordsLinked to original sources

PubMed2006

Lower haemoglobin level and subsequent decline in kidney function in type 2 diabetic adults without clinical albuminuria.

AIMS/HYPOTHESIS: Anaemia has been suggested to be an independent risk factor for subsequent progression of advanced diabetic nephropathy; however, the relationship between haemoglobin levels and progression of nephropathy in patients without clinical albuminuria is unknown. METHODS: We conducted this prospective hospital-based cohort study of 464 type 2 diabetic patients (149 women and 315 men, 55+/-13 [mean+/-SD] years of age) with serum creatinine <177 micromol/l (2.00 mg/dl) and urinary albumin : creatinine ratio <300 mg/g creatinine. GFR was estimated using the equation formulated by the Modification of Diet in Renal Disease Study group, refitted for Japanese individuals. Most patients had haemoglobin concentrations in the normal range (144+/-15 g/l), only modest renal impairment (GFR: 74.8+/-14.5 ml min(-1) 1.73 m(-2)), and normal urinary albumin levels (81.5/18.5% with normo-/microalbuminuria). The primary outcome measurement was the rate of change in GFR determined by regression analysis with GFR as a function of time. Patients were followed up for a mean observation period of 5.0+/-0.9 (range: 2.5 to 6.2) years. RESULTS: Univariate and multiple regression analyses yielded a significant association between the rate of change in GFR and baseline haemoglobin concentration. After adjusting for covariates, the rate of decline in GFR was significantly greater in patients in the lowest haemoglobin quartile (-3.27 ml min(-1) 1.73 m(-2) year(-1)) than in the third (-2.71 ml min(-1) 1.73 m(-2) year(-1), p = 0.024) and highest quartiles (-2.78 ml min(-1) 1.73 m(-2) year(-1), p = 0.046). CONCLUSIONS/INTERPRETATION: Lower haemoglobin concentrations in type 2 diabetic patients without clinical albuminuria may be a significant predictor of subsequent decline in GFR.

Adult↗

PubMed2005

A role of mast cells for hepatic fibrosis in primary sclerosing cholangitis.

We encountered four patients with overt primary sclerosing cholangitis (PSC) which were histologically classified into stage 2 or 3. We examined the expression of stem cell factor (SCF), a ligand of c-kit, in injured bile ducts by immunohistochemistry, and mast cells were identified by immunohistochemistry using anti-HMCT (human mast cell tryptase) and anti-c-kit antibodies to clarify their relation with portal fibrosis coincident with destroyed bile ducts. SCF was detected in the epithelia of most bile ducts in PSC, and many HMCT- and c-kit-positive mast cells were found in portal tracts. Image analysis showed more significant numbers of c-kit-positive mast cells per area of portal tract in PSC than in chronic hepatitis C, and they might increase from stage 2 to 3. c-Kit-positive cells infiltrated into the portal tracts with SCF-positive destroyed bile ducts, and c-kit mast cells should be investigated in detail to make a role for portal fibrosis in PSC.

Journal Article↗

PubMed2001

A comparative vibrational and NMR study of cis-cinnamic acid polymorphs and trans-cinnamic acid.

The IR and Raman spectra of the two polymorphic forms (58 degree- and 68 degree-forms) of cis-cinnamic acid were measured, and the spectral differences discussed on the basis of the crystal structures of the two forms. The IR bands related to the COOH group differ in the frequencies and band shape, reflecting differences in the hydrogen bonding between the two modifications. These spectra were compared with those of trans-cinnamic acid. The IR, Raman, and NMR spectra of the isotopic compounds, including the deuterated and 13C analogs of the cis and trans acids, were also recorded in the solid state and in solution to confirm the spectral assignments.

Cinnamates↗

PubMed2001

Molecular structure and vibrational spectra of phenolphthalein and its dianion.

Infrared (IR) and Raman spectra of phenolphthalein (PP) and its dianion form (sodium and potassium salts) were studied both in the solid state and in aqueous solution. Band assignments were carried out on the basis of the isotope shifts of the ring deuterated and 13C-substituted derivatives. Spectral analyses reveal that the PP dianion exists as mixtures of the benzenoid form (colorless) and the quinonoid form (colored) in the solid state and in aqueous solution, while the neutral PP solely takes the gamma-lactone form. This work provides the first vibrational spectroscopic evidence for the coexistence of the two species in the PP dianions.

Indicators and Reagents↗

PubMed2000

Hydra biological detection of biologically active peptides in rat cerebrospinal fluid.

The Hydra bioassay system utilizes a tentacle ball formation (TBF), a component of the feeding response of hydra, elicited by S-methyl-glutathione. TBF is modulated by many biologically active peptides in a specific way to individual peptides, and is useful in investigating biologically active peptides in a complex biological sample. We applied the hydra bioassay to explore a possible biologically active substance responsible for the decrease in the motor activity of the mice. The suppression of the CSF obtained from rats after exhaustive exercise was marked lower than that of sedentary rats. Addition of transforming growth factor-beta (TGF-beta), which is the only substance known to nullify TBF, to CSF of the sedentary rat reproduced this change in the suppression of the TBF. This system is useful to screen active peptides in small amounts of biological samples containing very low concentrations of peptides.

Animals↗

PubMed2000

Suppression of S-methylglutathione-induced tentacle ball formation by peptides and nullification of the suppression by TGF-beta in Hydra.

Tentacle ball formation (TBF) in Hydra elicited by S-methylglutathione (GSM) was modulated by a number of biologically active peptides. Hydra fed on Artemia, which had been hatched in a common salt solution supplemented with LiCl and ZnCl(2), easily induced TBF in response to GSM after pretreatment with trypsin. After Hydra were treated with 100 pg/ml trypsin for 10 min, the response to GSM (TBF) was sensitively suppressed by acidic fibroblast growth factor and other biologically active peptides for >10 h. Various peptides, but not transforming growth factor beta (TGF-beta), suppressed GSM-induced TBF in a specific pattern for each peptide. However, TGF-beta was unique in that it did not suppress the response to GSM, but nullified the suppressive effect of other peptides. Only active TGF-beta nullified the suppressive effect of the peptides, and the latent form of TGF-beta neither suppressed GSM-induced TBF nor nullified the suppressive effect of other peptides. Members of the TGF-beta family suppressed GSM-induced TBF. These results indicate that all peptides examined, except for TGF-beta suppressed the response to GSM in a manner specific to each peptide. This assay system would be useful in identification of biologically active peptides.

Animals↗

PubMed2000

Diazepam-binding inhibitor-like activity in rat cerebrospinal fluid after stimulation by an aversive quinine taste.

Cerebrospinal fluid (CSF) taken from rats after stimulation by an aversive quinine taste (hereafter called quinine CSF) administered into the fourth ventricle of mice suppressed their intake of 5% sucrose solution. We examined the effects of CSF on glutathione-induced tentacle ball formation (TBF) of hydra to determine the change in CSF components associated with aversive taste stimuli. The suppressive activity of quinine CSF on TBF in the presence of 3 microM S:-methyl-glutathione (GSM) was markedly lower than that of CSF obtained from control rats (control CSF). Pronase-treated quinine CSF had suppressive activity similar to that of control CSF. The active principle passed through an ultrafiltration membrane, with a molecular weight cut-off of 30 kDa, but not through one with a cut-off of 3 kDa. A peptide fragment of diazepam-binding inhibitor (DBI) nullified the suppression of TBF at 3 microM GSM by control CSF. The nullifying activity of quinine CSF was not observed after treatment with a benzodiazepine receptor preparation that was able to bind DBI. When flumazenil, a benzodiazepine receptor antagonist, was given to mice, the suppression of the intake of 5% sucrose solution by quinine CSF was partially reversed. It is suggested that quinine CSF contains a DBI-like substance.

Animals↗

PubMed1999

Transforming growth factor-beta activated during exercise in brain depresses spontaneous motor activity of animals. Relevance To central fatigue.

Intracerebroventricular administration into sedentary mice of the high molecular mass fraction of cerebrospinal fluid (CSF) from exercise-exhausted rats produced a decrease in spontaneous motor activity [K. Inoue, H. Yamazaki, Y. Manabe, C. Fukuda, T. Fushiki, Release of a substance that suppresses spontaneous motor activity in the brain by physical exercise, Physiol. Behav. 64 (1998) 185-190]. CSF from sedentary rats had no such effect. This suggests the presence of a substance regulating the urge for motion as a response to fatigue. A bioassay system using hydra, a freshwater coelenterate, showed an activity indistinguishable from transforming growth factor-beta (TGF-beta) in the CSF from exercise-fatigued rats, while not in that from sedentary rats. The increase in the concentration of active TGF-beta in the CSF from exercise-fatigued rat was also ascertained by another bioassay system using mink lung epithelial cells (Mv1Lu). Injection of TGF-beta into the brains of sedentary mice elicited a similar decrease in spontaneous motor activity in a dose-dependent manner. Increasing the exercise load on rats raised both the levels of active TGF-beta and the activity of depression on spontaneous motor activity of mice in the CSF of rats. Taken together, these results suggest that exercise increases active TGF-beta in the brain and it creates the feeling of fatigue and thus suppresses spontaneous motor activity.

Animals↗

PubMed1998

A single pre-training glucose injection induces memory facilitation in rodents performing various tasks: contribution of acidic fibroblast growth factor.

Effects of a pre-training intraperitoneal glucose injection on learning and memory were tested using two tasks: passive avoidance and Morris water maze. In the former task, mice that had received glucose 2 h prior (but not 1, 3, or 5 h prior) to a trial that combined acquisition with passive avoidance of foot shock showed a significantly increased retention latency when tested 24 h later. Thus, this effect was time-dependent, and it was also found to be dose-dependent by further experiment. In contrast, 2-deoxy-D-glucose and fructose had no such effect. In the Morris water maze task, glucose injection 2 or 3 h before a block of trials enhanced the spatial memory performance of mice. These glucose-induced memory-facilitation effects were abolished by an intracerebroventricular injection of anti-acidic fibroblast growth factor antibody 30 min before the glucose injection, suggesting a critical role for endogenous acidic fibroblast growth factor in this facilitatory effect. Furthermore, continuous intracerebroventricular infusion of acidic fibroblast growth factor in rats significantly increased retention latency (when tested repeatedly on successive days using a passive avoidance task). Our earlier studies demonstrated that brain acidic fibroblast growth factor is produced in the ependymal cells of the cerebroventricular system, and is released into the cerebrospinal fluid following either a meal or a (intraperitoneal or intracerebroventricular) glucose injection. This released acidic fibroblast growth factor also diffuses into the brain parenchyma, and is taken up by neurons in the hippocampus, hypothalamus, and elsewhere in the brain some 2 h after the meal or glucose injection. These and the present findings indicate (i) that pre-training glucose injection improves memory performance, and (ii) that acidic fibroblast growth factor, especially by its action within the hippocampus, is involved in this enhancement process.

Animals↗

PubMed1998

In situ potentiation of the glutathione-binding protein for the tentacle ball formation by a protease and efficient ingestion of prey in hydra.

Within minutes, brief treatment with trypsin potentiated tentacle ball formation in Hydra japonica, a new behavioral response to reduced glutathione. With the potentiation of this behavioral response, new glutathione-binding proteins were immediately detected after the trypsin treatment of live Hydra, indicating that trypsin activated the glutathione-binding protein in situ. Fixed brine shrimp (Artemia francisca) were more efficiently ingested in the presence of trypsin and S-methylglutathione (GSM) than in the presence of GSM alone, suggesting a biological role of this behavioral potentiation by trypsin in the feeding chain of Hydra. Ingestion of live A. francisca was significantly reduced in the presence of soybean trypsin inhibitor, suggesting that a protease, possibly released from the wounded prey, plays a role in the feeding in vivo. As for Hydra swallowing its captured prey, a small hydra head piece was isolated and measured as it crept along a thin nylon line; advancement of the head was the same in the presence of both GSM alone, and in that of GSM and trypsin together. Together, these results indicate that the chemoreceptor potentiated in situ by a trypsin-like protease specifically evokes tentacle ball formation resulting in an efficient transfer of prey on the tentacle to the mouth.

Animals↗

PubMed1997

Effects of gonadotropin, estrogen, and progesterone on c-mos gene expression in mouse oocytes in vivo and in vitro.

OBJECTIVE: To analyze the effects of gonadotropin and ovarian steroid hormones on the gene expression of c-mos in mouse oocytes. METHODS: The changes of c-mos messenger RNA (mRNA) levels in oocytes were examined after the administration of pregnant mare's serum gonadotropin (PMSG) in vivo, or after incubation with estrogen and/or progesterone in vitro. Five IU PMSG was injected intraperitoneally to female immature mice, and human chorionic gonadotropin was also injected intraperitoneally 48 hours after the PMSG injection, with or without mating with male mice. The oocytes were collected from follicles or oviducts at 24, 30, 36, 42, 48, 60, 72, and 84 hours after the injection. The RNAs were extracted from 5 oocytes at each time point, and a reverse-transcription polymerase chain reaction using specific primers to c-mos DNA was performed to measure the relative amount of c-mos mRNA. RESULTS: The c-mos mRNA in oocytes at 36 hours after the injection was 2.7 times higher than that at 24 hours. The c-mos mRNA level gradually decreased thereafter, and after ovulation the level was only 1/10 of the peak level. When the oocytes that were retrieved 24 hours after PMSG injection were incubated with 800 ng/ml estradiol 17-beta or 600 ng/ml progesterone for 120 minutes, the c-mos gene expression was significantly suppressed or stimulated, respectively, in comparison with the absence of these substances. CONCLUSION: Although the regulatory mechanism of c-mos gene expression in oocytes is still unclear because the result obtained from the in vitro study, that estrogen suppressed the c-mos gene expression directly, was inconsistent with the result of the in vivo study, that increases of both c-mos mRNA and estrogen occurred simultaneously with PMSG stimulation in the early phase of preovulatory oocytes, our present study revealed that gonadotropin and steroid hormones might affect c-mos gene expression in mouse oocytes indirectly and/or directly.

Animals↗

PubMed1997

Comparison of commercially available kits with standard methods for detection of Salmonella strains in foods.

Six commercial kits were compared with the U.S. Food and Drug Administration (USFDA) method and the Japanese standard method for Salmonella isolation in foods. When only Salmonella serovars were tested, many of the methods performed well; however, when foods were artificially inoculated, only the USFDA method and immunomagnetic separation coupled with the xylose-lysine-brilliant green agar method (MS-XLBG) could positively detect Salmonella serovars. All seven wild-type Salmonella serovars were detected by the USFDA method, and the MS-XLBG method detected salmonellae from six samples.

Bacterial Typing Techniques↗

PubMed1997

Intraoral minor salivary gland tumors: a retrospective study of 129 cases.

From 1970 to 1996, 129 cases of intraoral minor salivary gland tumors were diagnosed at the Department of Pathology, Nihon University School of Dentistry. The diagnosis of each case was based on the 1991 WHO classification. Eighty benign and 49 malignant minor salivary gland tumors were found in the approximately 9,300 oral biopsies submitted during the 27-year period. Pleomorphic adenomas were the most commonly histologic type of the benign tumors identified and 51% of the malignant tumors were diagnosed as mucoepidermoid carcinoma. The most common primary location of the tumors was the palate. Sixty percent of all tumors occurred in females and the peak age for incidences of all tumors was found in the third, fourth, sixth and seventh decades. These results were compared with those of the studies in different world population groups.

Adenoma, Pleomorphic↗

PubMed1997

aFGF, endogenous satiety substance, facilitates learning, memory and immune function in aging.

aFGF injection s.c. once a week into SAMP8 was begun at 3 weeks after birth and continued for 10 months. Saline was injected as a control. learning and memory and cellular immunological functions in the aFGF group were enhanced significantly, while those of the saline group deteriorated. 1. The number of cholinergic neurons was decreased by less than 20% and ChAT activity in individual neurons in the medial septum which send monosyonaptic terminals to the hippocampus was significantly decreased in the saline group, but not so much in the aFGF group. 2. The respective densities of muscarinic and aFGF receptors, on the hippocampal neurons were significantly higher in the aFGF group than in the saline group. 3. The LTP in hippocampal slice preparations was significantly facilitated in the aFGF group, but not in the saline group. 4. The DTH, (T cell immune response) measured at the end of the 2nd and 7th months were reduced in the 7th month as compared with the 2nd month in the saline group, but aFGF group protected against this reduction. 5. These results show that aFGF provides protection against impairment of not only learning and memory but also the DTH immunoreactivity in SAMP8.

Aging↗

PubMed1996

Protection against impairment of memory and immunoreactivity in senescence-accelerated mice by acidic fibroblast growth factor.

Subcutaneous injection of aFGF once a week into senescence-accelerated mice (SAM)P8 was begun at 3 weeks after birth and continued for 10 months. Saline was injected as a control. Learning and memory and cellular immunological functions in the aFGF group were enhanced significantly, while those of the saline group deteriorated. 1. The number of cholinergic neurons was decreased by less than 20% and choline acetyltransferase activity in individual neurons in the medical septum which send monosynaptic terminals to the hippocampus was significantly decreased in the saline group, but not so much in the aFGF group. 2. The respective densities of muscarinic and NMDA receptors and the aFGF receptor, i.e., FGFR-1 on the hippocampal neurons were also significantly higher in the aFGF group than in the saline group. 3. The long-term potentiation in the hippocampal slice preparations after a brief tetanic stimulation at the Schaffer collateral/commissural afferents was significantly facilitated in the aFGF group, but not in the saline group. 4. These data indicate the normalization caused by aFGF of the medial septohippocampal circuit, which is necessary for learning and memory. 5. The delayed type hypersensitivity reactions (DTH) in the footpad caused by challenge with trinitrophenyl or sheep red blood cells as measured at the end of the 2nd and 7th months, indicated the T cell immune response. Both types of DTHs were reduced in the 7th month as compared with the 2nd month in the saline group, but the aFGF group was protected against this reduction in accordance with age. 6. These results show that aFGF provides protection against impairment of not only learning and memory but also DTH immunoreactivity in SAMP8. They also indicate a close relationship between learning and memory and T cell immune function.

Aging↗

PubMed1996

Evaluation of cardiac function by echocardiography in dogs treated with doxorubicin.

Cardiac functions were evaluated by echocardiography in dogs treated with doxorubicin. The dogs were administered 1.5 mg/kg body-weight doxorubicin intravenously at intervals of 3 weeks. Two-dimensional echocardiography of several sections of the heart was taken and fractional shortenings of chordal and papillary muscle levels were measured from M-mode echocardiogram to assess the left ventricular contractile function. And color Doppler and pulse Doppler examinations of mitral flow velocity were performed. Concomitantly, electrocardiogram (ECG) was also examined. The animals with decreased cardiac function were euthanized and the hearts were examined histologically. Fractional shortening was reduced gradually in the dogs treated with doxorubicin. And mitral regurgitation during systolic phase and changes of mitral flow velocity during diastolic phase were also revealed in the dogs with severe reduction of fractional shortening. These changes might indicate the reduction of cardiac functions, both of contractility and diastolic filling functions. ECG abnormalities, which were small changes, revealed only in the dogs that had severe reduction of fractional shortening and mitral regurgitation. In histological examination, myocardial degeneration was observed. And, the degree of myocardial damage might be relative to alteration of fractional shortening. Thus, the result demonstrates that the early alteration of cardiac function induced with doxorubicin can be detected by echocardiography in dogs. The result also indicates that cardiac function predicted by fractional shortening measured from M-mode echocardiogram might be correlated with histological changes of myocardium.

Animals↗

PubMed1995

Actions of acidic fibroblast growth factor fragments on food intake in rats.

Acidic fibroblast growth factor (aFGF) has suppressive effects on food intake. In the present study, the effect of aFGF fragments on food intake were investigated in rats. Infusion of a carboxyl-terminal fragment of aFGF, aFGF-(114-140), did not affect food intake, whereas an amino-terminal fragment of aFGF, aFGF-(1-15), was significantly inhibitory. Other amino-terminal fragments, aFGF-(1-20), aFGF-(1-29) and aFGF-(9-29), did not affect food intake. However, [Ala16]aFGF-(1-29) and [Ser16]aFGF-(1-29) in which the cysteine residue at position 16 was replaced with alanine and serine, respectively, had significant suppressive effects on food intake. Infusion of a functional antagonist for FGF receptor, anti-FGFR-1 antibody, into the lateral hypothalamus (LHA) significantly increased food intake. The results suggest that: the amino-terminal portion of aFGF is active in food intake suppression; the replacement of cysteine residue by alanine or serine is important in some amino-terminal aFGF fragments; and the LHA is involved in feeding suppression actions by aFGF and some fragments.

Alanine↗

PubMed1995

Regulation of neuronal nitric oxide synthase in rat adrenal medulla.

Neuronal nitric oxide synthase (nNOS) has been suggested to be involved in cardiovascular homeostasis. We studied the regulation of nNOS expression, determining nNOS mRNA expression levels in various tissues in spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). We also investigated the effects of antihypertensive treatment with the angiotensin II antagonist hydralazine or reserpine on nNOS mRNA expression. The expression levels of nNOS mRNA and nNOS protein were determined by Northern and Western blot analysis, respectively. NADPH-diaphorase histochemistry was used to identify cells in the adrenal medulla that expressed nNOS. No significant differences in expression levels in SHR and WKY were observed in the cerebellum and brain stem. nNOS mRNA expression levels in the decapsular portion of the adrenal gland were developmentally modulated and in a 24-week-old WKY were 2.5 times higher than in an age-matched SHR. This reduced expression of nNOS mRNA in the decapsular portion of the adrenal gland of SHR seemed to be a result of hypertension in the SHR, because administration of either an angiotensin II antagonist (TCV-116) or hydralazine upregulated nNOS mRNA expression in both SHR and WKY. Marked augmentation of nNOS mRNA expression in the decapsular portion of the adrenal gland by reserpine treatment suggested an intimate relation between nNOS in the decapsular portion of the adrenal gland and the sympathoadrenal system. Reserpine treatment also increased the expression of nNOS protein; however, reserpine treatment did not affect the distribution pattern of nNOS-positive cells (NADPH-diaphorase-positive cells) in the adrenal medulla.(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Medulla↗