Biomedical subjects

T Terada

Publications and source records attributed to T Terada.

At least 235 records · Page 13Linked to original sources

PubMed1995

Regulation of the Osem gene by abscisic acid and the transcriptional activator VP1: analysis of cis-acting promoter elements required for regulation by abscisic acid and VP1.

Osem, a rice gene homologous to the wheat Em gene, which encodes one of the late-embryogenesis abundant proteins was isolated. The gene was characterized with respect to control of transcription by abscisic acid (ABA) and the transcriptional activator VP1, which is involved in the ABA-regulated gene expression during late embryo-genesis. A fusion gene (Osem-GUS) consisting of the Osem promoter and the bacterial beta-glucuronidase (GUS) gene was constructed and tested in a transient expression system, using protoplasts derived from a suspension-cultured line of rice cells, for activation by ABA and by co-transfection with an expression vector (35S-Osvp1) for the rice VP1 (OSVP1) cDNA. The expression of Osem-GUS was strongly (40- to 150-fold) activated by externally applied ABA and by over-expression of (OS)VP1. The Osem promoter has three ACGTG-containing sequences, motif A, motif B and motif A', which resemble the abscisic acid-responsive element (ABRE) that was previously identified in the wheat Em and the rice Rab16. There is also a CATGCATG sequence, which is known as the Sph box and is shown to be essential for the regulation by VP1 of the maize anthocyanin regulatory gene C1. Focusing on these sequence elements, various mutant derivatives of the Osem promoter in the transient expression system were assayed. The analysis revealed that motif A functions not only as an ABRE but also as a sequence element required for the regulation by (OS)VP1.

Abscisic Acid↗

PubMed1995

Partial nodular transformation of the liver with portal vein thrombosis. A report of two autopsy cases.

Partial nodular transformation (PNT) of the liver is a rare condition in which nonfibrous nodules composed of hyperplastic hepatocytes replace the hepatic parenchyma around the hepatic hilus. We report two autopsy cases involving PNT of the liver with portal vein thrombosis. Case 1 was a 27-year-old man with malignant lymphoma. Ascites gradually increased, and he died 4 years after the onset of his illness. Case 2 was a 73-year-old woman treated for cirrhosis for 4 years who died of renal failure. Postmortem examination of these two cases revealed numerous coalescent nodules in the hilus of the liver as well as portal vein thrombus in the hilus. Microscopically, these nodules in the perihilar area were composed of hyperplastic hepatocytes without fibrous rim, and the peripheral parenchyma showed atrophy to some extent. The portal vein thrombi in the hilus and large portal tracts were mainly fresh and partially organized. Portal vein branches in the peripheral small portal tracts were devoid of significant pathologic changes. We suggest that PNT of the liver in our cases occurred as the result of uneven blood supply to the perihilar parenchyma due to portal vein thrombosis in the hepatic hilus.

Adult↗

PubMed1995

Arterial elements and perisinusoidal cells in borderline hepatocellular nodules and small hepatocellular carcinomas.

Borderline hepatocellular nodule in the human cirrhotic liver is considered a preneoplastic lesion of hepatocellular carcinoma (HCC). However, the angiogenetic process and changes in perisinusoidal cells (fat-storing cells or Ito cells) during the borderline nodule-HCC sequence have not been investigated. We have investigated intraparenchymal arterial elements and perisinusoidal cells in normal livers, chronic hepatitis, borderline nodules and small HCC, using an immunohistochemical staining for alpha-smooth muscle actin. In normal livers, chronic hepatitis, cirrhotic nodules and large regenerative nodules, no or few arterial elements were present in the parenchyma, and alpha-smooth muscle actin-positive perisinusoidal cells were increased further. These data suggest that angiogenesis first occurs in borderline hepatocellular nodules and it gradually proceeds during the nodule to HCC sequence along with an increase in perisinusoidal cells. The demonstration of arterial elements and perisinusoidal cells may be useful for the differential diagnosis of large regenerative nodule, borderline hepatocellular nodule and small HCC.

Arteries↗

PubMed1995

Accelerated endothelial regeneration and intimal hyperplasia following a repeated denudation of rabbit carotid arteries: morphological and immunohistochemical studies.

1. We compared endothelial regeneration and intimal thickening after endothelial denudation between normal and sclerotic carotid arteries (CA). Endothelial denudation of the right CA of rabbits formed intimal thickening covered with regenerated endothelial cells (EC) in 6 weeks, which was considered as the sclerosis model. Both CA were then denuded. Morphological and immunohistochemical studies using antibodies for proliferating cell nuclear antigen (PCNA), von Willebrand factor and macrophages were performed. 2. Regeneration of EC were observed 24 h after denudation on both CA, but completed earlier in the double-denuded right CA. The density of EC in both CA increased after regeneration and gradually decreased afterwards. 3. After a single denudation on the left CA, PCNA-positive cells clearly appeared in 24 h, markedly increased in 72 h both in the intima and media, then greatly decreased in 4 and 6 weeks. 4. After a double denudation of the right CA, enhancement of the intimal hyperplasia was observed. PCNA-positive cells markedly increased in 1 week and remained significantly increased in 6 weeks both in the intima and the media. 5. We concluded from these results that the repeated endothelial denudation caused more sustained proliferation of smooth muscle cells which led to an enhancement of the intimal hyperplasia.

Analysis of Variance↗

PubMed1995

[Endovascular treatment of cerebral vasospasm with intra-arterial papaverine infusion].

Thirty-one cases of cerebral vasospasm following subarachnoid hemorrhage were treated with intraarterial papaverine infusion. Symptomatic cases were nineteen, and asymptomatic cases were twelve. Papaverine (120 mg/saline 50 ml, 30 min) was injected superselectively to vasospastic vessels through a microcatheter. The rate of symptomatically improved cases was 63% initially, but about two thirds of those cases had recurrence within a day. The 63% of symptomatic cases showed infarction in spite of papaverine infusion. Three cases of recurrent vasospasm after intra-arterial papaverine underwent PTA and showed good dilatation of vasospastic vessels. The complications of our intra-arterial papaverine were hypotension in two cases, convulsion in one case and transient disturbed consciousness in one case. We experienced no fatal complications. Overall outcome was ADL1 (19%), ADL2 (25%), ADL3 (44%), ADL4 (0%), ADL5 (6%), and death (6%). Since the effect of intra-arterial papaverine infusion is of short duration and weak, combination of PTA and papaverine may be necessary. It is recommended to use papaverine for vasospasm in distal arteries such as M2, A1, A2, and to carry out PTA for proximal arteries such as ICA and M1.

Adult↗

PubMed1995

[The effect on higher cortical dysfunction of percutaneous transluminal angioplasty for internal carotid artery stenosis].

Seven patients with internal carotid artery (ICA) stenosis with higher cortical dysfunction due to hemodynamic ischemia were treated by percutaneous transluminal angioplasty (PTA). The patients ranged from 49 to 71 years of age, and included five males and two females. Neuropsychological tests were evaluated before and after PTA. Higher cortical dysfunction improved in all cases after PTA. It is concluded that PTA is effective to improve higher cortical dysfunction in patients who have ICA stenosis associated with hemodynamic compromise, if the ICA is satisfactorily dilated.

Aged↗

PubMed1995

Expression of matrix proteinases during human intrahepatic bile duct development. A possible role in biliary cell migration.

Primitive biliary cells are known to migrate from the ductal plate into the mesenchyme during human intrahepatic bile duct development, and this migration process is essential for normal development of intrahepatic bile ducts. However, its molecular mechanism is unknown. Matrix proteinases play an important role in cell migration during cancer invasion and organ development. In this study, we therefore investigated in situ expression of matrix metalloproteinases (MMP) and tissue inhibitors of MMP (TIMP) during human intrahepatic bile duct development, using 32 human fetal livers. We also examined in situ expression of trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B, which are matrix proteinases and activators of MMP. MMP-1 expression was noted in the ductal plate and migrating primitive biliary cells. MMP-2, MMP-3, and MMP-9 were expressed in the ductal plate. TIMP-1 and TIMP-2 were expressed in the ductal plate and migrating primitive biliary cells. Trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B were also expressed in primitive biliary cells. These data suggest that MMP, trypsinogen/trypsin, chymotrypsinogen/chymotrypsin, and cathepsin B play a critical role in biliary cell migration during human intrahepatic bile duct development by degrading extracellular matrix proteins. The data also suggest that MMP inhibitors (TIMP-1 and TIMP-2) and MMP activators (trypsin, chymotrypsin, and cathepsin B) play an important role in biliary cell migration. The coordinated expression of MMP, MMP inhibitors, and MMP activators may be necessary for the normal development of human intrahepatic bile ducts.

Bile Ducts, Intrahepatic↗

PubMed1995

Detection of apoptosis and expression of apoptosis-related proteins during human intrahepatic bile duct development.

We investigated apoptosis by nick end labeling and the expression of apoptosis-related proteins by immunohistochemistry in fetal development of human intrahepatic bile ducts and hepatocytes. During intrahepatic bile duct development, apoptosis was present at all stages, and its positive ratio was high in the remodeling ductal plate, moderate in the ductal plate, and relatively low in remodeled ducts. The cell proliferative activity as determined by proliferating cell nuclear antigen was also high in the remodeling ductal plate, and relatively low in the ductal plate and remodeled ducts. fas antigen and c-myc protein were constantly positive in the ductal plate, remodeling ductal plate and remodeled ducts. Bcl-2 protein was negative or faintly positive in the ductal plate and remodeling ductal plate, but was apparently positive in remodeled ducts. Lewisy as detected by the BM-1 antibody was present in the ductal plate, remodeling ductal plate, and remodeled ducts. p53 protein was not found in any cell types in the liver development. During hepatocyte development, many apoptotic and proliferating cell nuclear antigen-positive hepatocytes were noted. The developing hepatocytes expressed c-myc protein and fas antigen. Bcl-2 protein and Lewisy antigen were also weakly positive in the developing hepatocytes. These findings showed that balanced cell proliferation and apoptosis are involved in the normal development of intrahepatic bile ducts and hepatocytes, and suggest that c-myc protein, fas antigen, Bcl-2 protein, and Lewisy antigen modulate apoptosis of fetal intrahepatic biliary cells and hepatocytes, probably by stimulative (c-myc protein and fas and Lewisy antigens) or inhibitory (Bcl-2 protein) effects.

Antigens, Surface↗

PubMed1995

Expression of glycoconjugates during intrahepatic bile duct development in the rat: an immunohistochemical and lectin-histochemical study.

We investigated the expression of carbohydrate residues on the developing intrahepatic bile ducts of rats. At 17 days of gestation, immature biliary cells around the portal vein close to the hepatic hilum assumed one of the following forms: slitlike lumen, incomplete, or complete bile ductule-like structures. These immature biliary elements then rapidly spread throughout the liver along with development. At birth, a few mature interlobular bile ducts became visible in the portal tracts. The cytoplasm of immature biliary cells stained weakly for concanavalin A, Erythrina crista galli agglutinin, and Limax flavus agglutinin, whereas the luminal surface of immature biliary cells at 17 days of gestation was positive for lectins, similar to those that are expressed on the luminal surface of the mature bile ducts, including concanavalin A, succinyl wheat germ agglutinin, Vicia villosa agglutinin, soybean agglutinin, peanut agglutinin, Erythrina crista galli agglutinin, and Limax flavus agglutinin. As development progressed, the number of lectins binding to the cytoplasm of biliary cells gradually increased, and lectin bindings to the luminal surface of biliary cells gradually became intense. Immature biliary epithelial cells of three structures expressed similar carbohydrate residues in their cytoplasm and luminal surfaces. This study suggested that the profile of carbohydrate residues on the biliary epithelium changes with development. Therefore, this profile could be a useful tool with which to evaluate the development of the biliary tree as well as associated disorders.

Aging↗

PubMed1995

[A case of spinal dural arteriovenous fistula associated with normal pressure hydrocephalus].

A 62-year-old male presented with urinary incontinence, gait disturbance and dementia for 6 months. Neurological examination revealed severe paraparesis (1/5), sensory disturbance below Th10, neurogenic bladder and absence of patellar and achilles tendon reflexes. CT scan showed mild brain atrophy and symmetric ventriculomegaly with periventricular lucency. Magnetic resonance imaging (MRI) showed a linear flow void lesion on the dorsal surface on the back of his swollen lower spinal cord. Myelography showed a filling defect and flow disturbance of contrast medium in lower thoracic levels, suggesting the presence of adhesive arachnoiditis. Spinal angiography demonstrated a fistula formation between dural branches of bilateral L4 lumbar arteries and ventral spinal and radicular veins on the surface of the dura mater of L4/5 levels. Considering his past history of repeated lumbar puncture for tuberculous meningitis at the age of 22 years, a diagnosis of acquired spinal dural arteriovenous fistula probably due to repeated lumbar puncture was made. Fistulas were embolized with N-butyl cyanoacrylate. And normal pressure hydrocephalus was treated by ventriculoperitoneal shunt. Follow-up CT scans showed a decrease of the size of the ventricular system. Etiology of acquired spinal arteriovenous fistula has been reported. In the case, repeated lumbar puncture may be a possible cause of arteriovenous fistula in the lower spinal dura mater. However, the reason why it took so long to form a fistula after the lumbar puncture remains to be elucidated. We suggest that an increased protein concentration due to disturbance of cerebrospinal fluid flow might be a cause of normal pressure hydrocephalus (NPH).

Arteriovenous Fistula↗

PubMed1995

Distribution of cytokeratin 19-positive biliary cells in cirrhotic nodules, hepatic borderline nodules (atypical adenomatous hyperplasia), and small hepatocellular carcinomas.

Borderline nodule (BN) in the cirrhotic liver is considered to be a precancerous lesion leading to hepatocellular carcinoma (HCC). We investigated the distribution of cytokeratin 19 (CK 19)-positive biliary cells, recognizable by a monoclonal antibody AE1, in normal livers, chronic active hepatitis, cirrhosis, BN, and small HCC. The CK 19-positive biliary cells in the hepatic parenchyma were clearly divisible into two types (I and II). Type I cells were located within the hepatic parenchyma as small clusters forming small tubules (intraparenchymal ductules). Type II cells were bile ductules located in the peripheral rim of the hepatic lobules or hepatocellular lesions (peripheral ductular reaction) and were continuous with proliferated bile ductules in fibrous septae or portal tracts. In chronic active hepatitis and regenerative nodules of cirrhosis, a few type I cells and a variable number of type II cells were present. In the BN, all cases harbored a few type I cells as well as a variable number of type II cells. The type II cells in the BN were fewer in number and more randomly distributed than those in chronic active hepatitis and cirrhosis. Malignant foci in some BNs lacked CK 19-positive biliary cells. In small HCC, no CK 19-positive biliary cells were found; instead, AE1-positive HCC cells were present in three cases (17%). Although a great majority of type I cells corresponded to intraparenchymal ductules, some type I cells in the BN were composed of rather large tubules considered as interlobular bile ducts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenoma↗

PubMed1995

Intrahepatic cholangiographic appearance simulating primary sclerosing cholangitis in several hepatobiliary diseases: a postmortem cholangiographic and histopathological study in 154 livers at autopsy.

Intrahepatic cholangiography of primary sclerosing cholangitis (PSC) is characterized by stricture with or without dilation of the biliary tree. To evaluate whether this cholangiographic appearance is present in non-PSC livers as well as the histological features seen in non-PSC livers with this cholangiographic appearance, we performed postmortem intrahepatic cholangiography in 154 liver autopsy specimens. The PSC-like cholangiographic appearance was frequently found in cirrhosis with or without hepatocellular carcinoma (4 of 6, 67%), hepatocellular carcinoma (1 of 1, 100%), adult-type polycystic disease of the liver and kidneys (2 of 3, 67%), submassive hepatic necrosis (2 of 5, 40%), amyloidosis (1 of 2, 50%), and intrahepatic extensive thrombosis (1 of 1, 100%). It was also found but at lower frequency in metastatic carcinomas (3 of 13, 23%) and leukemia/lymphoma infiltration (2 of 12, 17%). Histologically, in livers with such a PSC-like cholangiographic appearance, the intrahepatic bile ducts were compressed by fibrosis, inflammatory infiltrates, liver cysts, cancer cell infiltration, amyloid deposition, or portal thrombi. Dilated ducts had less pronounced changes than strictured ducts. In these hepatobiliary diseases, the changes of intrahepatic bile ducts in the livers without the PSC-like cholangiographic appearance were much less marked than those in the livers with it. These data suggest that the PSC-like intrahepatic cholangiographic appearance is present in several hepatobiliary diseases and that clinicians should take such diseases into consideration if stricture with or without dilation is found on intrahepatic cholangiography.

Adolescent↗

PubMed1995

[Slowly progressive memory impairment without generalized dementia--a clinical and radiological study].

We report a patient with a ten-year history of slowly progressive recent memory decline without additional cognitive impairment in presenility. A right-handed Japanese barber first experienced forgetfulness at the age of 59. Neurological examination at age 64 revealed no abnormality except for severe impairment in memorizing. Brain CT-scans were normal. In spite of gradually deteriorating memory, he was capable of organizing his work until the age of 67 years. At age 69, he showed intense recent memory defect and disorientation in time, but immediate memory span and remote memory beyond the retrograde gap were better preserved. Intelligence quotient (IQ) on the Wechsler adult intelligence scale-R remained 85 (verbal IQ, 88: performance IQ, 83). Neurological examination was negative. He showed no signs of aphasia, agnosia, or apraxia. Minimal organic personality changes were noticed. Brain CT-scans and MRI revealed mild atrophy of the temporal lobes and hippocampal formation on both sides. I123-IMP single photon emission computed tomography (SPECT) disclosed a decrease of cerebral blood flow in both the inferior temporal and superior frontal regions. SPECT after acetazolamide administration showed augmented accumulation in areas with decreased accumulation at baseline. Despite progressive memory impairment, the absence of aphasia, agnosia, or apraxia differentiates our case from more common Alzheimer's disease. A degenerative disorder of focal cerebral atrophy or "simple senile dementia" of presenile onset was suspected of causing the underlying pathophysiological changes.

Aged↗

PubMed1995

Biliary epithelial expression of MUC1, MUC2, MUC3 and MUC5/6 apomucins during intrahepatic bile duct development and maturation. An immunohistochemical study.

Phenotypic alterations of biliary epithelial cells such as changes in intermediate filament composition and presence of carbohydrate residues, occur during the development of intrahepatic bile ducts. In this study, we examined the expression of MUC1, MUC2, MUC3, and MUC5/6 apomucins (mucin core proteins) by immunohistochemical means in the human intrahepatic bile duct during its development and maturation. In the fetal liver, new bile ducts in the portal tracts, either at the hilar level (corresponding to the large bile ducts) or peripheral level (corresponding to the small bile ducts), frequently expressed MUC1 apomucin at their luminal surface. Ductal plates also focally expressed MUC1 apomucin. By contrast, in the postnatal liver, the biliary epithelial cells of intrahepatic large bile ducts constantly expressed MUC3 apomucin, whereas those of small bile ducts did not. MUC2 and MUC5/6 apomucins were absent in the intrahepatic biliary elements of the fetal as well as postnatal livers. These data suggest that the biliary epithelial cells switch MUC1 apomucin expression before birth to that of MUC3 after birth. This characteristic transition may be similar to the changes in the hepatocellular expression of alpha-fetoprotein and albumin during the perinatal period.

Adolescent↗

PubMed1995

Role of arginine residues of bovine liver dihydrodiol dehydrogenase 2 in the binding of anionic substrates.

Bovine liver dihydrodiol dehydrogenase (DD2) was inactivated following pseudo-first order manner by the treatment of 5 mM 2,3-butanedione (BD) as functions of incubation-time and concentration. Anionic substrates or analog which have a carboxyl group, D-glucuronate, p-carboxybenzaldehyde and D-glycerate, protected DD2 efficiently. But, the other substrates or coenzymes and their analogs did not show any protection on the inactivation, i.e., D,L-glyceraldehyde, D-erythrose, NADP+, NAD+, 2',5'-ADP, 2'-AMP. Results of kinetic analyses suggest that the inactivated enzyme lost its binding ability to anionic substrates. The inactivated enzyme was reactivated very effectively by removing excess BD by gelfiltration for 30 min.

Animals↗

PubMed1995

[Primary hemangiopericytoma of the chest wall: a case report].

We describe a rare male case of malignant hemangiopericytoma of the chest wall. An extrapleural chest wall mass about 1.5 x 4 cm in size was detected along the right 3rd rib on a chest roentgenogram when the patient was 58 years old. The tumor did not enlarge for over 12 years thereafter. At the age of 73 years, the patient came to our hospital for chest pain after a traffic accident. A roentgenogram revealed the extrapleural tumor of the chest, which was enlarged to 8 x 12 x 7 cm, and right hemothorax. The tumor was resected together with the 3rd and 4th ribs. Light and electron microscopy and immunostaining studies led to a diagnosis of malignant hemangiopericytoma. The postoperative course was uneventful, and radiotherapy and chemotherapy were performed. The patient has been well without recurrence for 18 months after the operation. We also reviewed 9 cases of this tumor reported in Japan.

Aged↗

PubMed1995

[Effects on cognitive function and activities of daily living after stereotactic thalamotomy for Parkinson's disease].

Stereotactic thalamotomy was performed in ten patients with Parkinson's disease for the suppression of their tremor. After VL-thalamotomy, contralateral tremor and rigidity disappeared or was significantly reduced. Activities of daily living (ADL) measured by functional independence measure and Parkinson's disability score were improved postoperatively in all patients. There was significant improvement in anxiety index. However, other neuropsychological tests showed no significant change postoperatively. ADL improved after thalamotomy. It is concluded that stereotactic VL-thalamotomy is a useful treatment which improves ADL without cognitive dysfunction.

Activities of Daily Living↗

PubMed1995

Cloning and characterization of a rat H+/peptide cotransporter mediating absorption of beta-lactam antibiotics in the intestine and kidney.

A complementary DNA (cDNA) encoding the rat H+/peptide cotransporter (PepT1) was isolated, and the transport characteristics of orally active beta-lactam antibiotics were assessed by measuring uptake into Xenopus oocytes expressing the rat PepT1. The rat PepT1 cDNA encoded a 710-amino acid protein with 77% identity to the rabbit PepT1. The message for rat PepT1 was approximately 2.9 kilobases and was found predominantly in the small intestine, whereas reverse transcription-polymerase chain reaction amplification revealed that the message was expressed both in the small intestine and in the kidney cortex. The 75-kDa protein was identified by translation of in vitro synthesized transcript of rat PepT1 cDNA by use of rabbit reticulocyte lysates and by Western blot analysis with a specific antibody against the rat PepT1. When expressed in Xenopus oocytes, rat PepT1 stimulated the uptake of ceftibuten (anion) and cephradine (zwitterion) in the presence of an inward H+ gradient, and the expressed uptake was inhibited by excess dipeptides. Kinetic analysis revealed that ceftibuten has 14-fold higher affinity for the rat PepT1 than cephradine. These findings suggest that the rat PepT1 mediates H(+)-coupled uphill transport of the oral beta-lactam antibiotics across the brush-border membranes of intestinal and renal proximal tubular cells.

Amino Acid Sequence↗