Biomedical subjects

T Deguchi

Publications and source records attributed to T Deguchi.

At least 235 records · Page 13Linked to original sources

PubMed1991

Localization of hydroxyindole O-methyltransferase-synthesizing cells in bovine epithalamus: immunocytochemistry and in-situ hybridization.

Hydroxyindole O-methyltransferase (HIOMT)-immunoreactive cells and melatonin synthesis were demonstrated in bovine epithalamus (including the pineal gland) with monoclonal antibodies and cRNA probes to HIOMT. The HIOMT-immunoreactive product was present in the cytoplasm of pinealocytes. All identifiable pinealocytes were clearly labeled in the pineal gland. The expression of the HIOMT gene was first identified in pinealocyte cytoplasm by in-situ hybridization (ISH). The distribution of the hybridization-positive cells in the pineal gland was compatible with that revealed by immunocytochemistry using the monoclonal antibody to HIOMT. In addition, HIOMT transcripts were found in the medial habenular nucleus, and the habenular and posterior commissure; they may correspond to S-antigen-immunoreactive cells demonstrated in the same regions of the hamster and the mouse. In these regions, the hybridization-positive cells did not exhibit HIOMT-immunoreactivity; thus, cells devoid of immunoreactivity may synthesize but rapidly transport the newly synthesized proteins. These results indicate (1) that the conversion of N-acetylserotonin into melatonin takes place in the cytoplasm of pinealocytes, (2) that some epithalamic cells in the habenular area may synthesize melatonin, and (3) that melatonin may act as a chemical messenger in centrally directed processes, as shown by using S-antigen immunocytochemistry.

Acetylserotonin O-Methyltransferase↗

PubMed1991

A case report of hepatocellular carcinoma within adenomatous hyperplasia: is adenomatous hyperplasia a precancerous lesion or not?

It is controversial whether adenomatous hyperplasia (AH) of the liver progresses to hepatocellular carcinoma. We experienced two hepatic lesions in a patient (73-yr-old male) with cirrhotic liver. One was diagnosed as HCC and the other was AH including a small HCC histologically. To investigate cell kinetics and the ploidy pattern of these lesions, Feulgen DNA-cytofluorometry analysis was performed. The result of this analysis suggested that AH developed into extremely well-differentiated HCC composed of mononuclear diploid cells at first and then was further transformed into clear cell type HCC composed of mononuclear tetraploid cells. The development of human HCC, at least in cirrhotic liver, may therefore be a multi-step process.

Aged↗

PubMed1991

Postbinding insulin resistance around parturition in the isolated rat epitrochlearis muscle.

To determine whether insulin resistance exists in maternal skeletal muscle during pregnancy and how it returns to normal during the postpartum period, 3-O-methyl[14C]-D-glucose transport and [125I]insulin-binding activities were measured in isolated rat epitrochlearis muscle. Maximally insulin-stimulated methylglucose transport activity was decreased on day 20 of pregnancy and on days 1 and 4 post partum; it returned to the nonpregnant level by day 9. The insulin-binding activity did not change significantly throughout pregnancy, increased on days 1 and 4 post partum, and returned to the nonpregnant level by day 9. There was no significant difference in insulin binding or insulin-stimulated methylglucose transport activity between lactating and nonlactating animals. These results suggest that insulin resistance caused by postbinding changes in epitrochlearis muscle develops during late pregnancy and continues at least until day 4 post partum. Lactation does not appear to have a significant effect on insulin resistance.

Adenosine Triphosphate↗

PubMed1991

Skeletal, dental, and functional effects of headgear-activator therapy on Class II malocclusion in Japanese: a clinical case report.

Ten orthodontic patients in whom a headgear-activator appliance was used in the first phase of treatment for Class II malocclusion were clinically evaluated. All patients had abnormal perioral muscle function at the initial examination. Myofunctional methods were used before and during active treatment. Pretreatment and posttreatment cephalometric tracings were evaluated to examine the effect of the appliance on dental, skeletal, and soft tissue structures. Five of the 10 cases illustrated distal movement of the lower first molar, a phenomenon not mentioned previously in the literature. Growth stimulation of the mandible was also observed in this patient sample, with some subjects demonstrating above-average mandibular growth when compared with a control group of normal subjects. Abnormal oral function was eliminated, and all patients had clinically acceptable results at the end of the treatment period. The headgear-activator appliance can be considered an effective tool for the control of vertical growth problems in growing mixed-dentition patients.

Activator Appliances↗

PubMed1991

[Detection of Chlamydia trachomatis by polymerase chain reaction].

A polymerase chain reaction (PCR) procedure was developed for detection of Chlamydia trachomatis. Two oligonucleotide primers based on sequences within the major outer membrane protein gene from C. trachomatis serovar L2 were used. A single DNA fragment was amplified, when C. trachomatis DNA was template for the PCR. No amplified product was detected in Chlamydia psittaci DNA, Chlamydia pneumoniae DNA or other bacterial DNAs. The amplified DNA fragment was detected, when DNA of greater than or equal to 10(2) C. trachomatis per reaction was used as template for the PCR. Thus, the PCR was shown to be specific for C. trachomatis and more sensitive than the enzyme immunoassays for detection of chlamydial antigen and the chlamydial rRNA:DNA probe hybridization method.

Chlamydia trachomatis↗

PubMed1991

[Detection of Chlamydia trachomatis from urethral swab in male urethritis by polymerase chain reaction].

A polymerase chain reaction (PCR) with Chlamydia trachomatis-specific primers was applied for detection of C. trachomatis from urethral swab in male urethritis. The results were compared with those of culture method for detection of C. trachomatis. Of 18 clinical specimens tested in this study, inclusion bodies of C. trachomatis were detected in 11 specimens by the culture method. For PCR, sample DNA was prepared from transport medium in which urethral smear was suspended and two oligonucleotides based on sequences within the major outer membrane protein gene from C. trachomatis serovar L2 were used as extension primers. In 12 of the 18 specimens, 242bp DNA fragment was amplified by PCR and demonstrated to be the DNA fragment of C. trachomatis by Southern blot hybridization. No DNA of 242bp was amplified by PCR from five specimens in which any inclusion bodies of C. trachomatis were observed or from a specimen in which one inclusion body per cover slip was detected by culture method. C. trachomatis DNA of 242bp was amplified from all specimens in which 14 and more inclusion bodies per cover slip were detected by culture method. In two specimens concluded s negative by culture method, amplified C. trachomatis DNA were detected by PCR. Thus, the PCR would be a more simple and sensitive method for detection of C. trachomatis, compared with the culture method.

Bacteriological Techniques↗

PubMed1991

In vivo effect of human granulocyte colony-stimulating factor derivatives on hematopoiesis in primates.

Using cynomolgus monkeys, we studied the hematopoietic effect and antigenicity of the human granulocyte colony-stimulating factor (hG-CSF) derivatives mutated at N-terminal amino acids (NC-59 and KW-2228) and that lacking N-terminal amino acids (M-7) in comparison with intact hG-CSF. These compounds were subcutaneously administered daily into the back of cynomolgus monkeys at the doses of 1 and 100 micrograms/kg for 2 weeks, and withdrawn for 2 weeks (1st course). After that, the same schedule was repeated (2nd course), and intact hG-CSF and KW-2228 were further administered for 2 weeks (3rd course). In the first course, all of the G-CSF derivatives showed excellent dose-dependent granulopoietic activities. In the 2nd course, however, the activities of NC-59 and M-7 were decreased and the elevations of binding and neutralizing antibody titers were observed. On the other hand, KW-2228 showed granulopoietic activities equal to or better than that of intact hG-CSF and had low antibody titer throughout all the courses.

Amino Acid Sequence↗

PubMed1991

[Development of behavior and sex differences in infants; with reference to the formation of sex role].

In order to observe the formation of sex role, an investigation was made on the development of behavior and sex differences in infants aged 1 to 6 at Fukuoka-city. The present study consisted of questionnaire on behavior of daily living and breeding, block construction test and coloring a drawing test. The parents instructed their infants to become masculine for males and feminine for females on the basis of traditional view. No sex differences were observed in construction ability of infants aged 4. Favorite colors were different according to sex.

Age Factors↗

PubMed1990

Inhibition by transforming growth factor beta of choline acetyltransferase stimulation in a co-culture of spinal cord and muscle cells from mice.

Choline acetyltransferase (CAT) activity increased 11-fold in co-cultures of spinal cord and muscle cells from fetal mice relative to cultures of spinal cord cells alone. The addition of transforming growth factor-beta (TGF-beta) to the medium at 30 pM throughout the culture period inhibited the increase of CAT activity in the co-cultures, but did not affect the activity in cultures of spinal cord cells alone. TGF-beta did not inhibit glutamic acid decarboxylase activity in the co-cultures. Other growth factors such as epidermal growth factor, fibroblast growth factor and beta-NGF had little or no effect on CAT activity. TGF-beta markedly inhibited the fusion of myoblasts to myotubes and the expression of marker enzymes for muscle differentiation. When TGF-beta was included during muscle culture and removed before inoculation with spinal cord cells, myoblasts did not subsequently form myotubes. CAT activity in the spinal cord cells, however, markedly increased in co-cultures with the undifferentiated myoblasts. When TGF-beta was added to the co-cultures after myotube formation was complete, the increase in CAT activity was inhibited according to the length of TGF-beta treatment. These results suggest that TGF-beta inhibits the muscle-induced stimulation of CAT activity by inhibiting the production, secretion and/or action of trophic factors from muscle.

Acetylcholinesterase↗

PubMed1990

Correlation between acetylator phenotypes and genotypes of polymorphic arylamine N-acetyltransferase in human liver.

Southern blot analysis was performed with genomic DNAs from 86 human subjects using the 32P-labeled cDNA for polymorphic arylamine N-acetyltransferase (EC 2.3.1.5) in human liver recently cloned in our laboratory. Three types of N-acetyltransferase gene were identified. Gene 1 contains a 5.5-kilobase (kb) KpnI fragment with a BamHI site; gene 2 contains a 5.5-kb KpnI fragment without a BamHI site; and gene 3 contains a 5.0-kb KpnI fragment with a BamHI site. The combination of these three genes generated five genotypes. Acetylator phenotypes were determined in 29 healthy volunteers by isoniazid loading tests, and they were classified as rapid (10 subjects), intermediate (16 subjects), or slow (3 subjects) acetylators. Rapid acetylators were homozygotes of gene 1. Intermediate acetylators were heterozygotes of either genes 1 and 2 or genes 1 and 3. There were two exceptional cases who were classified as intermediate acetylators but were homozygotes of gene 1. Slow acetylators were either heterozygote of genes 2 and 3 or homozygotes of gene 3. These results indicate that gene 1 corresponds to high N-acetyltransferase activity, while gene 2 and gene 3 give rise to low N-acetyltransferase activity.

Acetyltransferases↗

PubMed1990

Cloning and expression of cDNAs for polymorphic and monomorphic arylamine N-acetyltransferases from human liver.

To elucidate the molecular basis of human N-acetylation polymorphism, cDNA clones encoding human liver N-acetyltransferases (EC 2.3.1.5) were isolated from lambda gt10 cDNA libraries using the 32P-labeled cDNA of rabbit liver N-acetyltransferase recently cloned in this laboratory. Three types of cDNAs (D-14, O-7, and D-24) were isolated and their nucleotide sequences were determined, from which the amino acid sequences of human N-acetyltransferases were deduced. All the cDNAs coded for 290 amino acids. Between D-14 and O-7 cDNAs, there was only a single-base substitution in the coding region, which replaced glutamic acid in D-14 cDNA for glycine in O-7 cDNA. There were considerable differences between O-7/D-14 and D-24 cDNAs, with 80% homology in amino acid sequences. When the cDNAs were inserted into pEF321 expression vector and introduced into Chinese hamster ovary cells, N-acetyltransferase activity was expressed in three groups of the transfected cells. The activity in cells transfected with D-14 cDNA was only 9-17% of the activity in O-7 cells. Immunoblot analysis of the transfected cells indicated that the difference in the enzyme activity between O-7 and D-14 cells was possibly due to a difference in the amount of enzyme proteins. The substrate specificity of the expressed enzymes indicated that O-7 and D-14 cDNAs code for polymorphic N-acetyltransferase whereas D-24 cDNA codes for monomorphic enzyme. Southern blot analysis indicated that the polymorphic and monomorphic N-acetyltransferases were encoded in separate genes and that there was restriction fragment length polymorphism with KpnI digestion in the polymorphic N-acetyltransferase gene.

Acetyltransferases↗

PubMed1990

Effects of arginine derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells.

The effects of L-arginine (Arg) derivatives on soluble guanylate cyclase from neuroblastoma N1E 115 cells were examined. The Arg derivatives were modified at the -NH2, -COOH, C alpha-proton or guanidino group of Arg. Among the synthesized derivatives, eight compounds, i.e. the 5-(dimethylamino)-1-naphthalenesulfonyl (DNS) ones, especially N-cyclohexyl-2-(N-DNSamino)-5-guanidino-2-methylvaleramide and 1-[2-(N-DNSamino)-2-(2-imino-1,2,3,4,5,6-hexahydropyrimidin- 4-yl)acetyl]- piperidine, were found to inhibit the activity of crude guanylate cyclase in the 105,000 g supernatant fraction of the cell homogenate. The enzyme, partially purified by a column of Chelex 100 Na+, was also inhibited by these eight compounds. The mode of the inhibition was competitive. The Ki values were in the range of 2-8 microM for the enzyme in the 105,000 g supernatant fraction and 3-16 microM for the partially purified enzyme, in the presence of Mg2+ as a metal cofactor. In contrast, a new derivative, methyl 2-amino-5-guanidinovalerate (M Arg ME), as well as the Arg methyl ester (Arg ME) and Arg; were found to enhance the activity of the partially purified guanylate cyclase; KA values of M Arg ME, Arg ME and Arg were approximately 9, 4 and 3 microM respectively. From these results, the free guanidino group including 2-imino-1,2,3,4,5,6-hexahydropyrimidin-4-yl or 2-imino-1,2,3,4,5,6-hexahydropyrimidin-5-yl and modification of the --NH2 residue with a hydrophobic group such as DNS seemed to be essential for inhibition of the guanylate cyclase; however, the guanidino and --NH2 residue of Arg should be free for activation by these Arg derivatives.

Arginine↗

PubMed1990

Effects of phorone and/or buthionine sulfoximine on teratogenicity of 5-fluorouracil in mice.

Embryotoxicity and teratogenicity of 5-fluorouracil (5-FU) and modulation of its effect by the depletors of glutathione (GSH) were evaluated in mice. Pregnant ICR mice were intraperitoneally (i.p.) injected with 25 mg/kg of 5-FU on day 11 of gestation (vaginal plug = day 0). Mice were pretreated i.p. with 250 mg/kg of phorone, a GSH depleting agent and/or 200 mg/kg of buthionine sulfoximine (BSO, an inhibitor of GSH biosynthesis) 4 hours before dosing with 5-FU. Dams were killed on day 17 of gestation. Fetuses were examined for external malformations, especially limb malformations. Pretreatment with phorone or BSO decreased fetal weight and increased the frequency and severity of oligodactyly induced by 5-FU, as well as the reduction of maternal GSH levels. Combined use of 125 mg/kg phorone and 100 mg/kg BSO i.p. augmented growth retardation induced with 5-FU. Cotreatment with exogenous GSH, at a dose of 300 mg/kg injected intravenously, could not suppress the augmentative effects of phorone and/or BSO on 5-FU teratogenicity under these experimental conditions. These results indicate that the level of endogenous GSH is one of the factors which significantly affects teratogenicity of 5-FU.

Animals↗

PubMed1990

Electron microscopic study of acute retrograde pyelonephritis in mice.

A strain of Escherichia coli O6:H-, which was isolated from a patient with acute pyelonephritis, was used to produce ascending pyelonephritis in mice. The histologic features at the early stage of acute pyelonephritis and the pathways of bacterial invasion and distribution in the infected kidneys were studied by using transmission electron microscope. The histologic changes were characterized by degeneration and destruction of renal pelvic and tubular epithelial cells, and a massive infiltration of polymorphonuclear leukocytes. Bacteria invaded the pelvic surface and spread over the renal medulla and cortex by contiguity twelve hours after infection. It was also shown that bacteria ascended the tubules, multiplied in the tubular lumina, destroyed the tubular epithelial cells, and spread over the renal cortex by twelve hours. In addition, bacteria and leukocytes phagocytizing bacteria were present in the capillaries in the renal interstitium twelve hours after infection.

Acute Disease↗

PubMed1990

Complementary DNAs for choline acetyltransferase from spinal cords of rat and mouse: nucleotide sequences, expression in mammalian cells, and in situ hybridization.

Complementary DNA clones containing the entire coding region of choline acetyltransferase (ChAT) were isolated from the spinal cords of rat and mouse. The cDNAs of rat and mouse coded for 640 and 641 amino acids, respectively, and showed 95% mutual homology and 80% homology with the cDNA of porcine ChAT. Northern blot analysis revealed a single band of 4.4 kb in the spinal cord and brain in each species. Introduction of the cDNAs into Chinese hamster ovary cells and neuron-derived cell lines, N1E115 and NG108-15, expressed a high ChAT activity, which was inhibited by a specific ChAT inhibitor. In situ hybridization using the rat cRNA probe revealed specific labeling of the motoneurons in the spinal cord and neurons in various forebrain nuclei of the rat where the existence of cholinergic neurons has been demonstrated immunohistochemically.

Amino Acid Sequence↗

PubMed1990

Angiotensin-converting enzyme inhibitors: synthesis and biological activity of N-substituted tripeptide inhibitors.

A new series of highly potent angiotensin-converting enzyme (ACE) inhibitors, 1-(N2-substituted L-lysyl-gamma-D-glutamyl)octahydro-1H-indole-2-carboxylic acids, was synthesized; various acyl groups were introduced at the alpha-amino group of the N-terminal P1 Lys. The effect of the N2-acyl groups on in vitro inhibitory activity and oral antihypertensive effect was examined. All of the synthesized N-acyl tripeptides were found to have in vitro inhibitory activity at an approximately nanomolar level, and showed antihypertensive potency in renal hypertensive rats at a dose of 10 mg/kg, when administered orally. Among them, compounds 7e, g and 9f, i, m showed potent and long-lasting antihypertensive effects compared with enalapril (2a). Their structure-activity relationships are also discussed.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1990

[Relation between dentofacial skeletal patterns and the deflection of the roots of mandibular canine and premolars].

We conducted an investigation of the relation between dentofacial skeletal patterns and the deflection of the roots of mandibular canines and premolars. Data on root deflection, rated as mesial, distal, or undeflected, were obtained from orthopantomographs taken of 130 patients who were judged to meet certain criteria on their initial orthodontic examinations. The significance of the relation between these data and the dentofacial patterns, determined by radiographic cephalometric analysis, was then examined statistically. This determined that in cases of severe mandibular prognathism (ANB less than -2 degrees), the roots of 1st and 2nd premolars exhibited significantly more mesial deflection. This result suggests that the mesial deflection of these roots is caused by the differential growth rates of basal and alveolar bone in cases of severe mandibular prognathism.

Alveolar Process↗

PubMed1990

[Robustness of the analytic/holistic processing strategies in various cognitive tasks].

Robustness of the analytic/holistic processing strategies was examined in various cognitive tasks. The tasks in Experiment I were to classify facial patterns and verbal materials of different category structures into two categories. Stimuli were presented either with (thematization condition) or without a theme. Three types of strategies were discerned; consistently-analytic, consistently-holistic and optimal shifting. Experiment II was designed to test their performance in the Kagan type perceptual and memory identification tasks. The results from the two experiments showed that about 30% of the subjects adhered to either analytic or holistic strategy across tasks and experiments. They exhibited responses similar to the reflective and impulsive types. Approximately 40% of the subjects adjusted their strategies according to the task demands.

Acoustic Stimulation↗