Biomedical subjects

H Fukuda

Publications and source records attributed to H Fukuda.

At least 505 records · Page 28Linked to original sources

PubMed1995

The relation between an esophageal cancer and associated cancers in adjacent organs.

BACKGROUND: The relation between esophageal cancers and head and neck tumors was studied in order to improve the treatment results in patients with multiple cancers. METHODS: We reviewed the records of 3,375 patients with an indexed squamous cell carcinoma of the head and neck treated at our institution between 1960 and 1994; and 81 patients were found to have an associated esophageal carcinoma. Similarly, the records of 434 patients with an indexed esophageal cancer were reviewed; and 54 patients had cancers in other organs or in the residual esophagus. A total of 135 esophageal cancers with 154 synchronous or metachronous cancers were entered into the analysis. RESULTS: The risk of developing esophageal cancer was ten times higher in male patients with head and neck cancer than in female patients. Synchronous or metachronous esophageal cancer associated with head and neck cancer was most frequently seen with pharyngeal cancer (28/360 = 7.8%), followed by in the oral cavity (47/2148 = 2.2%). CONCLUSIONS: Better knowledge of the relation between an esophageal cancer and a head and neck cancer may lead to the early detection of subsequent small, potentially curable neoplasms sited in either the esophagus or the head and neck region.

Carcinoma, Squamous Cell↗

PubMed1995

Stimulation of glossopharyngeal and laryngeal nerve afferents induces expulsion only when it is applied during retching in paralyzed decerebrate dogs.

Stimulation of the oropharyngeal mucosa induces vomiting in humans, however, it has not been seen in animals. Thus, we attempted to induce fictive vomiting by stimulation of lingual and pharyngeal branch afferents of the glossopharyngeal nerve, and afferents of the superior and recurrent laryngeal nerves in paralyzed decerebrate dogs. The stimulation did not induce fictive vomiting when it was applied during eupnea, but induced fictive expulsion when it was applied during fictive retching. Threshold intensity for the induction decreased with the progress of retching.

Afferent Pathways↗

PubMed1995

[Psychological evaluation of out-patients in our pain clinic using self-rating depression scale and state-trate anxiety inventory questionnaire].

In 98 out-patients who visited our pain clinic, we evaluated their psychological status before the first examination and one month after the treatment, using self-rating depression scale (SDS) and state-trate anxiety inventory (STAI). SDS, state anxiety, and trate anxiety scores were significantly higher in the patients with pain (trigeminal neuralgia, neck-shoulder-arm pain syndrome, lumbago and psychological pain, n = 55) compared with the patients without pain (sudden deafness and facial nerve palsy, n = 43) (P < 0.01, 0.05, 0.01). Of the patients with pain, patients with psychogenic pain showed the highest score in every test. The scores of SDS and state anxiety became significantly lower one month after the treatments compared with ones before the first examination (P < 0.01). It was considered that the decline in every score was due to the treatments in our pain clinic. In patients whose score of trate anxiety before the first examination was more than 50 points, the SDS and state anxiety showed high scores even one month after the treatments. This finding suggests that these patients need psychosomatic managements.

Adult↗

PubMed1995

Polyunsaturated fatty acid regulation of lipogenic enzyme gene expression in liver of genetically obese rat.

The polyunsaturated fatty acid regulation of lipogenic enzyme gene expression in genetically obese rats (Wistar fatty, non-insulin-dependent diabetes mellitus) has been investigated. The hepatic mRNA concentrations and activities of lipogenic enzymes in the fatty and lean rat were greatly increased by feeding a hydrogenated fat diet to fasted rats, and also reached similar maximum levels with similar time courses. By feeding a corn oil diet, however, the increases were markedly reduced in the lean rats, but were not significantly reduced in the fatty rats. Consequently, when the animals were fed corn oil, the mRNA concentrations and activities in the fatty rats were higher than those in the lean. Thus, it appeared that the higher gene expression in the fatty rats can be ascribed to the defects of polyunsaturated fatty acid suppression. On the other hand, insulin binding to receptors in the liver was reduced by the corn oil diet in the lean rats but was not reduced in the fatty rats (although the insulin binding level was lower in the Wistar fatty rats than in the lean). Changes in the insulin receptor autophosphorylation and kinase activity toward exogenous substrate were similar to the insulin binding. It is suggested that the polyunsaturated fatty acids may not suppress insulin binding activity to receptors in the livers of the fatty rats, probably due to down regulation by hyperinsulinemia. The defects of polyunsaturated fatty acid suppression of lipogenic enzyme gene expression may be one of the factors of obesity.

Animals↗

PubMed1995

Functional diversity of GABAA receptor ligand-gated chloride channels in rat synaptoneurosomes.

Experiments were performed to examine neurochemically the functional diversity of GABAA receptors as measured by muscimol-, 5 alpha-pregnane-3 alpha,21-diol-20-one (THDOC)-, and pentobarbital-stimulated 36Cl- uptake, and region-specific changes in muscimol-, THDOC- and THDOC-induced potentiation of muscimol-stimulated 36Cl- uptake in rats treated acutely or subacutely with a subconvulsive dose of bicuculline. The data for stimulation of 36Cl- uptake by muscimol showed a single binding site interaction in the cerebral cortex, hippocampus and cerebellum. The concentration-response curves for muscimol in the cerebral cortex and hippocampus were steep and indicated an increase of approximately 130% at the maximum concentration. In contrast, the curve for the cerebellum was shallow and exhibited a smaller maximal response (approximately 60%). Apparent affinity for muscimol also differed among these brain regions. The regional differences in 36Cl- uptake induced by THDOC and pentobarbital were not as apparent as those induced by muscimol; however, the maximal modulatory effect of pentobarbital in the hippocampus was significantly higher than that in the cerebellum. In rats treated subacutely with a subconvulsive dose of bicuculline, a significant increase in muscimol-stimulated 36Cl- uptake was observed in the cerebellum but not in the frontal cortex or hippocampus. Analysis of the concentration-response curves for muscimol-stimulated 36Cl- uptake in the cerebellum revealed that the Vmax for muscimol in the subacutely treated group was significantly higher than those for muscimol in the control and acutely treated groups without any differences in the KD value.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1995

Isolation and characterization of homeobox-containing genes of carrot.

Homeodomains (HDs) are DNA-binding domains that have been well characterized in animals, and HD proteins are thought to be regulators of transcription. To investigate the regulation of gene expression during somatic embryogenesis in carrot, an attempt was made to isolate cDNA clones that encode HD proteins. A cDNA library from carrot somatic embryos was screened with a degenerate oligonucleotide probe that corresponded to a conserved amino acid sequence of HDs, and one cDNA clone (CHB1) encoding an HD protein was isolated. The amino acid sequence deduced from the nucleotide sequence of this clone contained a putative leucine zipper motif adjacent to the anticipated HD. The homeodomain/leucine zipper (HD-Zip) sequence of this cDNA was used for further screening, and five additional independent clones (CHB2 through CHB6) were isolated. Although the HD-Zip sequences encoded by these clones were similar to each other, the sequences beyond the HD-Zip regions varied greatly. Transcripts corresponding to CHB1 through CHB6 were expressed at different times during somatic embryogenesis. In particular, transcripts corresponding to CHB2 were expressed in close association with the early development of embryos.

Amino Acid Sequence↗

PubMed1995

Isolation of a carrot gene expressed specifically during early-stage somatic embryogenesis.

We report the first successful isolation by subtractive hybridization of a gene expressed specifically during somatic embryogenesis. Embryogenic cell clusters, 32-50 microns in diameter, were isolated by sieving and density-gradient centrifugation. The cDNA library was constructed from proglobulars which were formed from embryogenic cell clusters 3 days after transfer to auxin-free modified Lin and Staba's medium. For use as probe in screening, the same cDNA used for library construction was enriched for specific sequences using subtractive hybridization. The cDNA used for subtraction was prepared from suspension cultures 5 days after subculturing in auxin-containing medium. Nine independent differentially expressed cDNA clones were obtained from a screen of 150,000 recombinant phages. Northern analysis indicated one of these, CEM6, to be expressed specifically during somatic embryogenesis. In addition, one hybridizing transcript was detected in plantlet cotyledons, and two transcripts were detected in hypocotyls. Two separate and distinct hybridizing transcripts are expressed specifically in hypocotyl tissue. The amino acid sequence deduced from the nucleotide sequence of the CEM6 cDNA indicates that it encodes a glycine-rich protein containing a hydrophobic signal-sequence like domain. Its early embryo-specific expression and sequence characteristics suggest an important role as a cell wall protein in embryogenesis.

Amino Acid Sequence↗

PubMed1995

Improvement of S-adenosylmethionine production by integration of the ethionine-resistance gene into chromosomes of the yeast Saccharomyces cerevisiae.

An ethionine-resistance gene cloned from Saccharomyces cerevisiae DKD-5D-H was able to enhance S-adenosyl-L-methionine (AdoMet) accumulation when it was introduced into the yeast cells on multi-copy plasmid YEp13. In order to increase the AdoMet accumulation, the gene was integrated into the yeast chromosome by using a yeast transposon Ty element. When the YEp plasmid was used for the integration, the ethionine-resistance gene was efficiently inserted into the yeast chromosomes with a substantial increase in AdoMet productivity (about twofold) in comparison with that by the yeast cells carrying the gene on an extrachromosomal multi-copy plasmid.

Biotechnology↗

PubMed1995

The detection of the mRNAs of procollagen types I, II and III in human fetal fingers by in situ hybridization using digoxigenin-labelled oligonucleotide probes.

Messenger RNAs (mRNAs) encoding procollagen alpha 1 type I,alpha 1 type II and alpha 1 type III have been localized in paraffin sections of human fetal fingers using digoxigenin-labelled synthetic oligonucleotide probes. The probe-mRNA hybrids were visualized using an anti-digoxin antibody amplified with sandwich techniques. These protocols provided an excellent hybridization signal with minimal background noise. The sensitivity of the protocols was nearly equivalent to that seen when using isotopic cDNA probes. In human fetal fingers, intense hybridization signals for procollagen alpha 1 type I mRNA were detected in the osteoblasts and the fibroblasts of periosteum and perichondrium, the tenocytes of tendons, fibroblasts of ligaments, the synovial membrane and deeper layers of the dermis. In contrast, positive hybridization signals for procollagen alpha 1 type II mRNA were visualized in chondrocytes and the cambial layer of perichondrium. The signals for procollagen alpha 1 type III mRNA were detected in the fibroblasts of the dermis and perichondrium. The probes which have lower melting temperatures (Tm) could not detect the corresponding mRNAs.

Base Sequence↗

PubMed1995

A report on the perinatal diagnosis of 4 cases of cardiac tumors.

Since 1973, we have identified 4 cardiac tumors by ultrasonography in fetal or early postnatal life. Tuberous sclerosis was diagnosed in three infants whose mother was also affected. The first infant died from acute cardiac failure after birth, and the second required cardiac surgery. The third infant had a cardiac tumor and a focal seizure at the age of 8 months. The cardiac tumor disappeared at the age of 2 years. The fourth cardiac rhabdomyoma may be the only sign of tuberous sclerosis.

Diagnosis, Differential↗

PubMed1995

A developmental study of the synovial membrane of the rat temporomandibular joint: changes in the three-dimensional configuration during postnatal development.

The development of synovial membranes in the posterior synovial portion of the rat temporomandibular joint was studied and the three-dimensional structure of the posterior synovial portion reconstructed from sagittal semithin sections. Reconstructions showed that the synovial membrane expanded and that synovial folds increased in number and became complicated in shape with the growth of the joint. Using transmission-electron microscopy, it was observed that the synovial lining cells degenerated, that the synovial membrane split to make further synovial folds, and that the folded-end structures consisted of synovial lining cells that extended into the subsynovial connective tissue. It is suggested that in the development of the three-dimensional configuration of the synovial membrane, several processes proceed simultaneously to form the synovial folds: a splitting of the synovial membrane, infolding of the synovial membrane into the subsynovial connective tissue, and outgrowth of the synovial folds towards the synovial cavity.

Animals↗

PubMed1995

Error analysis of table look-up method for cerebral blood flow measurement by 123I-IMP brain SPECT: comparison with conventional microsphere model method.

While N-isopropyl-p-[123I]iodoamphetamine (IMP) is commonly used as a flow tracer, significant clearance from the brain causes underestimation of CBF as compared with true CBF when conventional microsphere model analysis is applied. We previously reported a simple "table look-up" method for CBF measurement using IMP taking into account this clearance effect. The method is based on a two-compartment model, the K1 (corresponding to CBF) and k2 constants being obtained from a table from the ratio of the 1st SPECT (40 min) to the 2nd SPECT (180 min) counts. Arterial input data used were obtained by one point blood sampling 10 min after IMP infusion against the standard input function. In the present study, this approach was compared with conventional microsphere model analysis. For 30 subjects, the latter method entailed 8 min continuous arterial blood sampling after IMP infusion and the use of SPECT data at the end of this period, calibrated by a count ratio of 8 min/40 min planar images of whole brains. A good correlation was observed between the two methods (r = 0.88), but an overestimation of table look-up method CBF as compared with microsphere model CBF was observed contrary to theoretical predictions. Limitations in the estimation of SPECT data at 8 min, obtained with SPECT data at 40 min for calibration of the count ratio of 8 min/40 min whole brain planar images, might be responsible for this.

Amphetamines↗

PubMed1995

Error analysis of autoradiography method for measurement of cerebral blood flow by 123I-IMP brain SPECT: a comparison study with table look-up method and microsphere model method.

N-isopropyl-p-[123I]iodoamphetamine (IMP) has been commonly used as a cerebral blood flow tracer, but, significant clearance of IMP from the brain to the blood causes underestimation of cerebral blood flow (CBF) as compared with true CBF when the conventional microsphere model method is applied. Previously, we reported an "Autoradiography method" (ARG method) for measuring CBF by using IMP in which this clearance effect was corrected. This method was based on a two-compartment model (influx: K1, efflux: k2, K1/k2 = distribution volume of IMP (Vd)), the K1 (corresponding to CBF) being obtained form the table which showed a correlation between CBF and the brain counts of SPECT scan with a constant Vd value. Arterial input data used were obtained by one point blood sampling 10 min after IMP infusion against the standard input function. In the present study, the ARG method was compared with the table look-up method (TLU method) and the conventional microsphere model method (MS method) for 30 subjects. When the Vd value in the ARG method was assumed to be 50 ml/ml, CBF values obtained by the ARG method were correlated well with those obtained by the TLU method (Y = 1.04X-2.5; X: TLU, Y: ARG r = 0.97) and those obtained by the MS method (Y = 0.82X + 12.1; X: ARG, Y: MS, r = 0.84). But, when the Vd value was assumed to be more or less than 50 ml/ml, ARG method CBF were under- or overestimated compared with the TLU method. This indicated that the ARG method could be a reliable method for CBF measurement if the Vd was determined properly. CBF values obtained by the MS method were actually 13.2% higher than those obtained by the ARG method against previous studies. As reasons for this, errors in the effects of gray-white matter mixture in the ARG method and in estimation of the SPECT brain counts at 8 min in the MS method were considered.

Amphetamines↗

PubMed1995

Inhibition of Na+/H+ exchanger attenuates neutrophil-mediated reperfusion injury.

BACKGROUND: The effect of Na+/H+ exchange inhibition in neutrophil-induced reperfusion injury was investigated using a new amiloride analogue, 5-methyl-N-isobutyl amiloride (MIA). METHODS: Rat neutrophils were separated using Percoll gradient. Luminol chemiluminescence intensity of isolated neutrophils was depressed by MIA in a dose-dependent manner. RESULTS: The effect of MIA on neutrophil-induced reperfusion injury was evaluated in Langendorff-perfused rat hearts subjected to 30 minutes of normothermic ischemia. Postischemic left ventricular developed pressure recovery was depressed by the reperfusion with neutrophils (60% +/- 7% to 33% +/- 26%) and was reverted by MIA pretreatment (86% +/- 17%, p < 0.05). MIA also improved percent recovery of coronary flow (51% +/- 2% to 70% +/- 13%), reduced creatine kinase (0.28 +/- 0.1 to 0.085 +/- 0.03 IU.L-1.g-1 dry wt), and lactate dehydrogenase leakage (10.6 +/- 3.8 to 5.16 +/- 1.3 IU.L-1.g-1 dry wt) significantly. The incidence of reperfusion-induced ventricular fibrillation also was reduced by MIA. CONCLUSIONS: The inhibition of Na+/H+ exchange shows a protective effect against neutrophil-induced reperfusion injury possibly by inhibiting the activation of neutrophils.

Amiloride↗

PubMed1995

Adenosarcomas originating from sites other than uterine endometrium.

We report three cases of adenosarcomas arising from extraendometrium of the uterus: one arising from the ovary, one from the paracolpium and one from the endocervix of the uterus. Microscopically, they consisted of an admixture of benign-appearing epithelial and mesenchymal components with hypercellularity and minimal atypia. Two of the tumors were initially misdiagnosed as endometriosis and one was diagnosed as adenofibroma. One patient had several recurrences and died 7 years after the initial laparotomy and another patient had sarcomatous overgrowth which invaded the muscular tissues of the large intestine. Thus it appears that adenosarcoma occasionally shows grave clinical behavior, despite the benign or low-grade appearance of its microscopic features. Problems of diagnosis and management of this tumor are discussed. An aggressive therapeutic approach including wide surgical excision is recommended even in questionable cases.

Adenosarcoma↗

PubMed1995

Pharmacology of descending noradrenergic systems in relation to motor function.

The function of descending noradrenergic systems in the spinal ventral horn has not been fully elucidated. We have reviewed our own findings and those of others relating to motor function of these noradrenergic systems. We studied the effects of adrenergic drugs on spinal reflexes, decerebrate rigidity, and noradrenaline release from the spinal cord in rats, and motoneuron activity in spinal cord slices isolated from adult rats. It was shown that the descending noradrenergic systems were facilitatory to the motor system, and that alpha 1-antagonistic action at the spinal cord and alpha 2-agonistic action at the brainstem inhibited spinal motor activity by blocking spinal alpha 1-receptors and by reducing the release of noradrenaline in the spinal cord, respectively.

Adrenergic Fibers↗

PubMed1995

Activation of peripheral and/or central chemoreceptors changes retching activities of Bötzinger complex neurons and induces expulsion in decerebrate dogs.

Fictive expulsion can be induced by electrical stimulation of the carotid sinus nerve during fictive retching or by discontinuing artificial ventilation in decerebrate paralyzed dogs. Both the phrenic and abdominal muscle nerves discharge during the early phase of fictive expulsion, but only the abdominal muscle nerve continues to discharge during the late phase. To determine whether Bötzinger complex (BOT) neurons participate in expulsion, responses to sinus nerve stimulation were examined in 47 non-respiratory (N-RES), 15 inspiratory (INS) and 12 expiratory (EXP) BOT neurons during eupnea. About 80% of the neurons produced excitatory or inhibitory responses. FIring patterns were observed in 61 N-RES, 39 INS and 56 EXP BOT neurons during expulsion induced by sinus nerve stimulation or by discontinuation of artificial ventilation. An activity pattern similar to that of the phrenic nerve was exhibited during fictive retching and expulsions by 13 N-RES< 3 INS and 8 EXP neurons, and a firing pattern like that of the abdominal muscle nerve was produced by 11 N-RES, 6 INS and 5 EXP neurons. Bursts were limited to the late phase of expulsion and to the period just after expulsion in 5 N-RES, 3 INS and 3 EXP neurons, and in 8 N-RES and 21 EXP neurons, respectively. Firings of the two latter groups of neurons decreased concomitantly with each retch or during retching. These results suggest that neurons of the two latter groups play crucial roles in the central patterning of neuronal expulsion activities.

Animals↗

PubMed1995

Dissecting thoracic aorta and fusiform aneurysm of the abdominal aorta.

A 59-year-old woman with dissection of the thoracic aorta and a fusiform aneurysm of the abdominal aorta without evidence of Marfan's syndrome underwent aneurysmorrhaphy with a bifurcated expanded polytetrafluoroethylene graft. Histological specimens of the aneurysmal wall revealed the presence of idiopathic cystic medial necrosis. As typical findings of idiopathic cystic medial necrosis in the aortic wall are very rare except in cases of Marfan's syndrome, the present case is reported and the implications of this condition are discussed.

Aortic Dissection↗