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Biomedical subjects

H Fukuda

Publications and source records attributed to H Fukuda.

At least 847 records · Page 47Linked to original sources
PubMed1989

Free combined anterolateral thigh flap and vascularized iliac bone graft with double vascular pedicle.

Although free vascularized iliac bone graft has been successfully used for the reconstruction of large bone defect with microvascular surgery, there is a serious problem of how to repair in one-stage, those cases having a large bone defect with a very wide skin defect. A free combined anterolateral flap and vascularized iliac bone graft with double vascular pedicles seems to be a most suitable method for cases having both large bone and skin defects. Two case reports are presented in which this flap was used. Based on the authors' cases, the advantages of this flap are its thinness and the extreme wideness of the skin territory. The anatomy of the pedicle vessels is large and long, and the donor scar can be made in an unexposed area. This flap can be considered for use in one-stage reconstructions of both large bone and skin defects in the oral and leg regions.

Aged↗
PubMed1989

Kinetic studies on the inhibition mechanism of diamine oxidase from porcine kidney by aminoguanidine.

The mechanism of inhibition of diamine oxidase [DAO, histaminase, amine: oxygen oxidoreductase (deaminating) (copper-containing), EC 1.4.3.6] by aminoguanidine was studied kinetically. The DAO reaction was carried out with putrescine as a substrate in the presence of o-aminobenzaldehyde and followed by the continuous increase in A430. An enzymatic reaction product, 4-aminobutyraldehyde, was spontaneously cyclized to delta 1-pyrroline, which coupled with o-aminobenzaldehyde to give rise to a yellow quinazolinium chromophore [Holmstedt et al. (1961) Biochim. Biophys. Acta 48, 182-186]. First, to measure the initial velocities as accurately as possible, the kinetic relationship between the oxidase reaction rate and the color development rate was formulated. The reaction proceeded linearly in the absence of aminoguanidine, but slowed down time-dependently in its presence. When the color development velocities in the presence of the inhibitor were plotted against time, the plot was nonlinear and there seemed to be at least two phases of the inhibition. Nonlinear least-squares analysis of the data dA430/dt showed that the simplest model that fitted best was a model composed of two species of enzyme-inhibitor complexes: E + I k+1 in equilibrium k-1 EI k+2 in equilibrium k-2 E'I where E is the enzyme, I is aminoguanidine (an inhibitor), and the ks are the rate constants.(ABSTRACT TRUNCATED AT 250 WORDS)

Aldehydes↗
PubMed1989

Enhancement of spinal monosynaptic reflexes with phenylethylamine and related drugs through descending noradrenergic neurons.

The effects of phenylethylamine (PEA) and related drugs, such as methamphetamine, phenelzine, methylphenidate, nomifensine and mazindol on the spinal monosynaptic reflex (MSR) were investigated in rats treated with 6-hydroxydopamine (6-OHDA) or 5,6-dihydroxytryptamine (5,6-DHT). PEA (1 x 10(-5) mol/kg, i.v.) increased the amplitude of MSR in control rats, but decreased the amplitude in rats treated with 6-OHDA. Although PEA-related drugs increased the amplitude of MSR, they did not change the MSR amplitude in 6-OHDA-treated rats. In 5,6-DHT-treated rats, PEA-related drugs increased the amplitude of MSR, whereas PEA produced a decrease. These results support our previous suggestion that the enhancement of MSR by these drugs might be mediated through release of noradrenaline or inhibition of noradrenaline uptake at the noradrenergic synapses.

5,6-Dihydroxytryptamine↗
PubMed1989

Structure-activity relationships of phenylethylamine analogs in their serotonergic depressant effects on the spinal monosynaptic reflex in rats.

The effects of 2-phenylethylamine (PEA) and related compounds on the spinal monosynaptic reflex (MSR) were examined using C1-spinalized rats. At low doses, PEA, S(+)-amphetamine, S(+)-methamphetamine and phentermine increased the amplitude of the MSR, whereas high doses of these drugs reduced it. p-Substituted PEA analogs (p-C1-PEA, p-methoxy-PEA and (+/-)-p-C1-amphetamine) only reduced the MSR. Low doses of PEA-related rigid compounds, R(+)-2-aminotetralin, (+/-)-N-methyl-2-aminotetralin and (+/-)-N,N-dimethyl-2-aminotetralin only reduced the MSR. S(-)-2-Aminotetralin did not affect the MSR. Depressions of MSR produced by PEA, S(+)-methamphetamine and R(+)-2-aminotetralin were antagonized by ketanserin and haloperidol which have 5-hydroxytryptamine (5-HT) antagonistic activity, and the MSR depression caused by S(+)-methamphetamine but not PEA and R(+)-2-aminotetralin was abolished by intracisternal 5,6-dihydroxytryptamine treatment or chronic spinal transection. These results suggest that PEA-related compounds cause MSR depression by direct and indirect 5-HT agonistic mechanisms, and support the proposal that the PEA moiety which exists in R(+)-2-aminotetralin is important for the direct 5-HT agonistic activity of some hallucinogens.

Animals↗
PubMed1989

Electrokinetic chromatography for drug analysis. Separation and determination of cefpiramide in human plasma.

Electrokinetic chromatography using a fused silica capillary and sodium dodecyl sulfate (SDS) solution has been applied to the separation and determination of cefpiramide (CPM) in human plasma with the use of antipyrine (AP) as an internal standard. A plasma sample was introduced into the capillary by siphoning. The calibration plot for CPM in plasma sample showed good linearity in the concentration range over 10 to 300 micrograms/ml. This method has advantages over usual high performance liquid chromatography (HPLC) in that it needs only a very small volume (less than 10 nl) of plasma without pretreatment, and an extremely high separation efficiency (10 times or much higher plate number than usual HPLC) is obtained. The addition of SDS to the supporting electrolyte solution enabled (1) rapid release of protein-bound drug which allowed the total concentration to be determined, (2) reproducible results to be obtained by suppressing adsorption of protein onto the fused silica capillary and (3) rapid separation of drug from proteins by selective retardation of protein peaks.

Cephalosporins↗
PubMed1989

Dependency of histamine induced phasic and tonic contractions on intracellular and extracellular calcium in guinea pig tracheal smooth muscle.

Dependency of histamine induced phasic and tonic contractions on intracellular and extracellular calcium in guinea pig tracheal smooth muscle was investigated. In Ca++-free Krebs-Ringer solution, the phasic contraction caused by 10(-5)M histamine was not affected, but the tonic contraction declined much faster than that in normal Krebs-Ringer solution (KR). The phasic contraction in KR containing 3 x 10(-4) M dantrolene was depressed, but reached a level similar to that in normal KR, and the tonic contraction was maintained similarly with or without dantrolene. In KR containing organic calcium channel blockers, 10(-5) M nilvadipine (FR34235), 10(-5) M verapamil or 10(-5) M diltiazem, neither phasic contraction nor tonic contraction was affected. No contraction was observed in Ca++-free KR containing 3 x 10(-4) M dantrolene. These results suggested that the phasic contraction by histamine depended on the intracellular calcium and the tonic one, on the extracellular calcium, and the organic calcium channel blockers had no effect on both phasic and tonic contractions caused by histamine.

Animals↗
PubMed1989

[Case of the maxillofacial defect patient. Prosthetic treatment after reconstruction of the palate and face using deltopectral flap].

The patient, a 72-year-old edentulous man, had an extensive maxillofacial defect caused by treatment of the maxillary cartinoma. As his left maxillary and zygomatic bone, a portion of the soft palate, orbital cavity contents and soft tissues of the cheek had been excised, his face was ugly, and his speech and eating were extremely poor. For this patient, first of all, plastic surgeons reconstructed the cheek and palate using deltopectral flap. Secondly, dentists prepared a facial prosthesis and a set of complete dentures. Four months after prosthetic treatment, plastic surgeons corrected the left corner of the mouth using temporal muscle flap and fascia lata, and strengthened infraorbial region of deltopectral flap by grafting the left 5th rib. Lastly, dentists remade the facial prosthesis. As a result, the patient had great improvement in his face, speech and eating. Periodic examination of the surgical site can be practiced through the remaining facial defect. The advantages of the surgical reconstruction in this case were as follows. (1) As reconstruction of the cheek narrowed a facial defect, it was easy to improve patient's appearance by a small facial prosthesis. (2) The closure of the palate was effective to improve hypernasal speech, to prevent fluid leakage into the nasal cavity and to improve the retention and stability of the upper complete denture.

Aged↗
PubMed1989

A clinical study on T1 glottic cancer treated by laser technique.

It is commonly accepted that radiotherapy is a first choice for treatment of T1 glottic cancer. However, side effects caused by irradiation are sometimes troublesome to a patient and to a physician. Among side effects, oncogenic problem and late radiation change are most undesirable and may become fatal. Hence, we avoid radiation therapy especially for younger aged patients. We prefer surgical therapy to radiotherapy for such a case. In our clinic, laser therapy has been employed. A laser beam is introduced through an operation microscope and a lesion can be microscopically vaporized. In this study, a survey of 40 patients with T1 glottic cancer submitted to laser surgery was reviewed. From those patients 25 were T1a and 15 were T1b. From our experience, laser vaporization is recommendable for T1 glottic cancer in younger aged patients. However, in order to obtain cure rate comparable to radiation therapy, the indication must be correctly designated.

Adult↗
PubMed1989

[Age-related cerebral white matter changes on computed tomography].

Changes of cerebral white matter on computed cranial tomography related to aging were studied in 70 subjects aged 30 to 94 years. The subjects had no histories of cerebrovascular accidents and no abnormalities in the central nervous system were shown by physical examinations nd CT scans. We measured the average attenuation values (CT numbers) of each elliptical region (165 pixels, 0.39 cm2) in the bilateral thalamus and twelve areas of deep white matter. Multiple regression analysis was used to assess the effects of age, cranial size and cranial bone CT numbers on the brain CT numbers. We also studied the association between brain CT numbers and brain atrophy, hypertension, diabetes mellitus. CT numbers of frontal white matter surrounding anterior horns decreased with aging in 70 subjects aged 30 to 94 years. No significant correlation between age and brain CT numbers was found in any other region by multivariate analysis, because of the prominent effect of cranial bone CT numbers on brain CT numbers. Although no age-related changes of white matter CT numbers was found in 41 subjects aged 30 to 65 years, there were significant negative correlations between age and white matter CT numbers at all regions in 29 subjects aged 66 to 94 years. Brain atrophy was associated with brain CT numbers. No association was found for hypertension or diabetes mellitus. Brain CT numbers decreased with aging even in neurologically healthy persons in older age. Brain CT numbers also decreased as cerebral atrophy advanced.

Adult↗
PubMed1989

[Double tracer whole body autoradiography using a short-lived positron emitter and a long-lived beta emitter].

We investigated glucose and amino acid metabolism in tumors and other organs using whole body autoradiography with a short-lived positron emitter and a long-lived beta emitter. The radioactive compounds used were 2-deoxy-2-[18F]-fluoro-D-glucose (18F-FDG) with a half life of 109.8 min and L-[methyl-14C]-methionine (14C-MET) with a half life of 5,730 years. A Donryu rat weighing about 150 g was subcutaneously inoculated at the back with experimental tumors of AH109A and AH272. 74 MBq (2 mCi) of 18F-FDG and 740 kBq (20 microCi) of 14C-MET was administered and after 30 min, the rat was sacrificed. Whole body frozen sections were obtained using autocryotome. For the 18F-FDG autoradiogram, the frozen sections were exposed to an X-ray film for 6 h. After seven days, these frozen sections were again exposed to 14C-MET for a week. Cross-contamination was minimized by adjusting the exposure time, the interval of exposures and the administered dose. The accumulation of the tracers was represented as the optical density ratio of the tissue of interest to the muscle. The tumor ratios were 12.5 for 18F-FDG and 8.6 for 14C-MET showing the highest accumulation in the whole body autoradiogram. In contrast the inflammatory tissue ratios were 1.27 for 18F-FDG and 0.77 for 14C-MET showing very low amino acid metabolism. With the present double tracer whole body autoradiogram, 18F-FDG accumulation was seen in the brain and the heart but not to the liver as against 14C-MET accumulation which was seen to the liver but not to the brain and the heart.

Animals↗
PubMed1989

[Successful treatment of advanced hypopharyngeal cancer with combination chemotherapy (VPCP regimen) followed by subsequent radiotherapy: a case report].

This report concerns a 64-year-old male suffering from advanced hypopharyngeal cancer. This patient was treated with four courses of combination chemotherapy including VPCP (a combination of VCR, PEP, CDDP and PEP) regimen as neo-adjuvant chemotherapy. And radiotherapy was given as a secondary treatment; Linac. 60 Gy/6 weeks. He showed no tumor masses in the hypopharynx following this combination chemotherapy. No recurrence has been found under endoscopy for one year after the treatment with combination chemotherapy. It thus seems that neo-adjuvant chemotherapy prior to surgery and/or radiation including cisplatin, peplomycin and other agents is very useful as a multimodal treatment for cancer of the hypopharynx.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1989

[Study on the concentration of 5-hydroxyindoleacetic acid (5-HIAA) in the lumbar cerebrospinal fluid (CSF) in neurological diseases].

Experimental evidence has shown that the amount of 5-HIAA in the CSF reflects the metabolism of serotonin in the brain if this metabolite is eliminated from the brain and flows into the CSF at a constant rate. We studied the concentration of 5-HIAA in the lumbar CSF in several neurological diseases to elucidate the alteration in abnormalities of serotonin metabolism. The concentration of 5-HIAA in the CSF was measured in 94 patients with cerebral infarction, 30 with vascular dementia, 25 with dementia of the Alzheimer type, 28 with Parkinson's disease and 6 with hypoxic encephalopathy. Patients with cerebral infarction were classified into 24 with a solitary cerebral infarct and 70 with multiple cerebral infarcts. Patients with Parkinson's disease were subdivided into 12 with various psychiatric symptoms including depressive state, hallucination and/or intellectual impairment and 16 without psychiatric symptoms. Patients with hypoxic encephalopathy consisted of 5 with apallic syndrome and one patient with Lance-Adams syndrome. The concentration of 5-HIAA in solitary cerebral infarct, multiple cerebral infarcts and vascular dementia did not exhibit a significant difference from that in control cases (54.6 +/- 23.1 ng/ml). But patients with dementia of the Alzheimer type (34.5 +/- 10.9, p less than 0.001) showed a significantly lower concentration. This fact seems to reflect the pathological finding that the number of large neurons is decreased and neurofibrillary tangles are increased in the nucleus raphe dorsalis of patients with Alzheimer type dementia.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Age-related decrease of 11C-N-methylspiperone in vivo binding to human striatum detected by PET].

The effect of aging on 11C-N-methylspiperone binding to living human striatum was demonstrated using positron emission tomography. The 11 normal volunteers (22 to 72 years old) participated in this study. The uptake of 11C-N-methylspiperone in the brain following intravenous injection was highest in the striatum in individual subject. And the uptake in the striatum only gradually increased until the end of the study. The uptake of 11C-N-methylspiperone in cerebellum peaked within 10 minutes following injection and then rapidly dropped. The association rate constant "k3" was calculated from the slope of the radioactivity-ratio of striatum to cerebellum versus the equivalent time. The equivalent time was calculated from the radioactivity of cerebellum as an input function. The exponential decrease of the k3 value with aging was observed. The k3 value of the youngest subject (22 years old, male) was 0.035/min, while that of the oldest one (72 years old, male) was found to be 0.020/min. These data suggested that the dopaminergic activity through D2 dopamine receptors reduces with aging in human striatum.

Adult↗
PubMed1989

Relationship between histologic type of primary lung cancer and carbon-11-L-methionine uptake with positron emission tomography.

L-[Methyl-11C]-methionine [( 11C]methionine) has proved to be one of the useful amino acids for the diagnosis of human cancer. We examined whether there was any correlation between [11C]methionine uptake and histologic type of primary lung cancer. Sixteen patients with nine squamous cell carcinoma, five large cell carcinoma, one small cell carcinoma, and one adenocarcinoma were studied using positron emission tomography (PET). All patients had high accumulation of [11C]methionine in lung tumors. We evaluated [11C]methionine uptake into the tumor by a semiquantitative value, DUR (Differential Uptake Ratio). There was significant difference (p less than 0.01, Mann-Whitney test) of [11C]methionine uptake between large cell carcinoma (3.98 +/- 0.27) and squamous cell carcinoma (2.92 +/- 0.30). The result suggested that there was correlation between [11C]methionine accumulation and the histologic type of lung cancer. This indicates a new potential applicability of [11C]methionine PET for the study of lung cancer.

Adenocarcinoma↗
PubMed1989

Tumor-localizing properties of porphyrins. In vitro studies using the porphyrin precursor, aminolevulinic acid, in free and liposome encapsulated forms.

Tumor, liver, skin and brain explants from tumor-bearing mice were cultured for 6, 12 and 22 hours in the presence of 0.06, 0.1 and 0.2 mM aminolevulinic acid (ALA). It was found that in all organs, synthesis of porphyrins increased with time and ALA concentration. The synthesising activity of tumor was high, of the same order as that of liver, and nearly twice that of skin and brain. The tissue/tumor porphyrin concentration ratios were lower than 0.5 at longer times and higher ALA concentration. In the case of skin/tumor the lowest ratio was about 0.2 and was obtained with 0.2 mM ALA. Chromatographic analysis of individual porphyrins showed that the whole heme pathway was functional in all organs studied, including tumor. Porphyrin synthesis by different organs from tumor bearing and normal mice was comparatively investigated using free and liposome encapsulated ALA. After 22 hours of incubation with 0.4 mM ALA, porphyrin formation was greater when encapsulated ALA was used. Accumulation of porphyrins in tumor was very high. The levels of activity were the same in each pair of organs in either the tumor-bearing mice or the control. These results indicate that free or encapsulated ALA may be used for the detection of tumors and in photodynamic therapy.

Adenocarcinoma↗
PubMed1989

[The oxygen dependence of the energy state of cardiac tissue--31P-NMR and optical measurement of myoglobin in perfused rat heart].

The relationship between the energy state and intracellular oxygen concentration was established in the cardiac tissues, where the former could be monitored by 31PNMR and latter by optical method for myoglobin absorption. The ratio of creatine phosphate to inorganic phosphate (PCr/Pi), started to fall at 40 microM ofintacellular oxygen concentration. In contrast, intracellular pH and cardiac function started to fall at 10 microM of oxygen. By infusion of epinephrine (0.01 micrograms/min), myoglobin was deoxygenated concomitant with the increase of left ventricular pressure and heart heart rate increased. The oxygen dependence of Parameters described above were unchanged by epinephrine infusion. Araki et al. reported that oxygen consumption, the reduction of pyridine nucleotide, the increase of lactate release started to change at 10 microM and reduction of cytochrome a + a3 started to increase at 40 microM. These results suggest that there is near-equilibrium state in the respiratory chain and oxidative phosphorylation in the cardiac tissue. The decrease of oxygen consumption was compensated by PCr/Pi ratio and cytochrome a + a3. And this near-equilibrium was maintained when the respiratory rate increased.

Animals↗