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Biomedical subjects

R Watanabe

Publications and source records attributed to R Watanabe.

At least 181 records · Page 10Linked to original sources
PubMed1995

Mucinous cholangiocarcinoma featuring a unique microcystic appearance.

An autopsy case is presented of a peculiar type of intrahepatic mucinous adenocarcinoma with microcyst formation arising in a 78 year old Japanese man who died of hepatic coma and renal failure 4 months after onset. Macroscopically, the cut surface of the lesion revealed a characteristic honeycomb-like appearance, consisting purely of microcysts, 0.2-0.4 cm in diameter, lined by prolific mucin-producing adenocarcinoma cells. The lesion did not have large cystic space, fibrous capsule, or benign cystadenomatous component other than neoplastic microcyst formation. The carcinoma cells showed various proliferating patterns, such as irregularly shaped nest-like, trabecular, papillary and tubular ones, directly invaded the hepatic parenchyma and portal tract with loose or thick fibrosis, and infiltrated extensively into both intrahepatic and extrahepatic stroma along the vascular structures. From these clinicopathological findings, we consider the present tumor to be a variant of mucinous cholangiocarcinoma with characteristic microcyst formation rather than a type of cystadenocarcinoma.

Aged↗
PubMed1995

[Investigation on change of acquired antibodies in responders against hepatitis B vaccine].

Changes of titers of acquired hepatitis B surface (HBs) antibodies against HB vaccine were investigated by measuring them again after a long lapse of time. Ten micrograms of the recombinant HB vaccine was intramuscularly injected respectively to the staff of the authors' hospital three times. Four weeks after a full course of the vaccination 185 persons could acquire antibodies, whose titers were 2.0 or more in cut off index (C.I.) by radioimmunoassay (RIA). Of these members titers of antibodies of 48 subjects could be remeasured for the first time 38 months after the measurement of the titers in the 4th week after a full course of the vaccination. Four weeks after the last vaccination 7 persons were high responders whose titers of antibodies were 50 or more in C.I. 29 were medium responders with their titers from 49 to 10, and 12 were low responders having titers of less than 10. However, 38 months after the course the titers of those responders decreased so much that nobody remained highly responders, 22 were low responders, and the remaining 22 turned to be negative again with titers less than 2.0. Supposing that the titer of antibody enough to protect the infection of HB virus is 10 or more in C.I., 32 of 36 persons needed booster shots 38 months later because their titers dwindled down to less than 10.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Reduced muscle uptake of oxygen during exercise in patients with systemic lupus erythematosus.

OBJECTIVE: To assess the factors limiting aerobic exercise capacity in patients with systemic lupus erythematosus (SLE). METHODS: The anaerobic threshold (AT) and O2 pulse, i.e., VO2/heart rate (HR), were measured in 21 patients with SLE without cardiopulmonary complications by the analysis of expired gas during incremental work load in exercise testing. The relationships between work rate (WR) and VO2, HR and VO2/weight (Wt), and lupus activity index (LAI) and AT were analyzed. RESULTS: The AT of the patients with SLE was significantly lower than for a control group. Little increase in O2 pulse and very low delta VO2/delta WR and delta VO2/Wt@delta HR were found during work load in some patients with SLE, especially those with a low AT and high LAI. Patients with SLE with a high LAI tended to show a low AT. CONCLUSION: The low aerobic exercise capacity of patients with SLE appeared to be mainly due to a small increase in O2 pulse. This may have resulted from impaired oxygen diffusion in the inflamed peripheral muscles in patients with active SLE. Low AT may explain in part why patients with SLE become easily fatigued.

Adult↗
PubMed1995

[Puerperal secondary pulmonary hypertension in a patient with mixed connective tissue disease].

A woman with mixed connective tissue disease (MCTD) developed pulmonary hypertension after delivery of a child, but had little evidence of parenchymal lung disease. This 29-year-old woman had been given a diagnosis of MCTD when she was 19 years old. She was admitted to our department two days after delivery of a child, because of dyspnea on exertion. Acute thromboembolism was suspected because of: (1) chest roentgenogram showing cardiomegaly and enlargement of the left main pulmonary artery, (2) a lung perfusion scan showing a segmental defect in the left S6 and S8 areas, (3) laboratory studies showing abnormally high WBC, LDH, FDP, and D-D dimer, and (4) arterial blood gas analyses showing mild hypoxemia and hypocapnia. Thrombolytic therapy with heparin and urokinase was begun, and was followed by a loop diurtic and anticoagulation with warfarin. One month after admission, cardiac enlargement and the A-aDO2 were found to have decreased. At that time, cardiac catheterization was done and revealed pulmonary hypertension (mean PA pressure: 45 mmHg) and low cardiac output with no detectable thrombosis in the left pulmonary artery. The patient was subsequently treated with a calcium antagonist and a prostacyclin derivative, and her condition was stable for 5 months. Then her exercise tolerance gradually decreased due to shortness of breath, and cardiomegaly gradually increased over the next 3 months. Eight months after delivery of the child, the patient died of right heart failure. In clinically stable patients with MCTD, delivery of a child may lead to pulmonary thromboembolism and pulmonary hypertension.

Adult↗
PubMed1994

Elastin in the human posterior longitudinal ligament and spinal dura. A histologic and biochemical study.

STUDY DESIGN: A histologic and biochemical study of elastin in the posterior longitudinal ligament and spinal dura was performed using autopsy cadavers. OBJECTIVE: To provide a rationale for resiliency of the PLL and the spinal dura. SUMMARY OF BACKGROUND DATA: Among the spinal ligaments, the nuchal ligament and the ligamentum flavum have a very high elastin content, and some biochemical and morphologic studies of these ligaments have been published. No reports on the elastin content in the posterior longitudinal ligament or spinal dura have been published. METHODS: Specimens of the posterior longitudinal ligament and the dura collected from three cadavers were studied histologically. For quantitative analysis of elastin and collagen, the posterior longitudinal ligament specimens were collected from 22 cadavers and the dura specimens from 20 cadavers. Elastin was extracted using the hot alkali method of Lansing et al. RESULTS: The elastic fibers in the posterior longitudinal ligament generally were arranged parallel in the cephalocaudal direction, whereas the fibers in the spinal dura had a more multidirectional arrangement. The elastin content of the posterior longitudinal ligament averaged 7.3% of the total dry weight and that of the spinal dura was 7.1% for the ventral aspect and 13.8% for the dorsal aspect. The elastin content of the spinal dura was about two times higher in all dorsal specimens than in the corresponding ventral specimens. The elastin content of the lower thoracic region was higher than that of any other region. The amino acid composition of the elastin in the posterior longitudinal ligament and spinal dura was similar to that previously determined in other spinal ligaments.

Aged↗
PubMed1994

A cloned rat CD38-homologous protein and its expression in pancreatic islets.

Cyclic ADP-ribose recently has been suggested to be an important intracellular signal for insulin secretion. CD38, which was originally isolated from human lymphocytes as a surface marker, is active in the synthesis of cyclic ADP-ribose. We report here the cloning of a rat CD38-homologous protein (CD38H) which is expressed in pancreatic islets. The deduced amino acid sequence shows that rat CD38H is a protein of 303 amino acids (M(r), 34.4 kD) and contains one possible membrane-spanning domain, consistent with a type II transmembrane glycoprotein. The overall identity and similarity of the amino acid sequences between the human CD38 and the rat CD38H are 58% and 76%, respectively. RNA blot analysis showed a strong signal of 3.4 kb in rat brain, duodenum, and heart. CD38H also is shown to be expressed in pancreatic islets by the RT-PCR procedure, but its expression is not significantly different in Wistar and GK rats, a genetic model of non-insulin-dependent diabetes mellitus. The presence of rat CD38H in the pancreatic islets suggests that CD38H may be involved in insulin secretion by synthesizing cADP-ribose.

ADP-ribosyl Cyclase↗
PubMed1994

mRNA and protein expression of p53 mutations in human bladder cancer cell lines.

We investigated mRNA and protein expression in p53 gene mutations in four human bladder cancer cell lines using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and Northern blot and Western blot analyses. The following mutations were identified in three of the four cell lines: a missense transversion at codon 110, a missense transition at codon 250 and a non-sense transversion at codon 126. These mutations were located outside previously identified hot spot codons and have rarely been reported in bladder cancer tissues or other neoplasms. Positive intranuclear p53 immunostaining in neoplastic cells in the two missense mutations and the premature stop codon in the non-sense mutation suggested the presence of structural and functional alterations in the p53 protein. Northern and Western blot analyses revealed either an intense or a weak p53 mRNA band together with an intense p53 protein band in the missense mutations, but no p53 mRNA or protein band in the non-sense mutation. A weak p53 mRNA band, but no distinct p53 protein band was observed in the cell line without a mutation and in normal control bladder cells. Our findings suggest that regulation of p53 expression in these cell lines differs at the post-transcriptional and/or post-translational level between the wildtype and the mutant p53 genes and also among different mutant p53 genes. The three cell lines with mutations were derived from high-grade carcinomas; the cell line without mutation was derived from a low-grade carcinoma.

Base Sequence↗
PubMed1994

Cerebellar hemorrhage complicating cervical durotomy and revision C1-C2 fusion.

STUDY DESIGN: A case of cerebellar hemorrhage complicating cervical durotomy and revision C1-C2 fusion is reported. There has been only one report on cerebellar hemorrhage after cervical durotomy. SUMMARY OF BACKGROUND DATA: The patient became comatose approximately 16 hours after surgery. According to a review of the recovery room records, the patient's cerebellar hemorrhage probably occurred some time within the first 10 hours after the procedure and not during the operation. METHODS: The authors reviewed reports on complicated cerebellar hemorrhage, and the causative factors were studied. CONCLUSION: Postoperative drainage of cerebrospinal fluid, especially when negative pressure is applied, may play a role in the occurrence of cerebellar hemorrhage.

Aged↗
PubMed1994

Molecular cloning of a cDNA encoding a novel fatty acid-binding protein from rat skin.

A novel skin-type fatty acid-binding protein, termed cutaneous(C)-FABP, has been purified from rat skin and a cDNA clone for this protein has been identified. The purified protein had the ability to bind long chain fatty acids like other rat FABPs. The deduced amino acid sequence of the cDNA clone comprises residues yielding a molecular mass for the polypeptide of 15.1 kDa and exhibits around 50% identity to myelin P2 protein, adipocyte FABP and heart FABP. Our results propose that C-FABP is a new member of the FABP family.

Adipocytes↗
PubMed1994

Involvement of ribonuclease III in the enhancement of expression of the speF-potE operon encoding inducible ornithine decarboxylase and polyamine transport protein.

Since the speF-potE operon (pPT71 clone) encoding inducible ornithine decarboxylase (iODC) and polyamine transport potE protein is inducible at acidic pH, a gene encoding a protein involved in the enhancement of expression of the operon was searched for. Using the fused gene containing the upstream sequence of the speF-potE operon and the open reading frame of beta-galactosidase as a reporter gene, a clone (pPTS23) which causes the increase of beta-galactosidase activity at acidic pH was isolated. The clone also increased iODC activity at acidic pH and was identified as a gene encoding RNase III. This is the first example that RNase III increases the translational efficiency of mRNA derived from Escherichia coli gene by cutting the 5'-untranslated region of mRNA.

Antiporters↗
PubMed1994

Hypertrophic spinal pachymeningitis.

A patient with idiopathic hypertrophic spinal pachymeningitis (HSP) with predominant involvement of the cervical and thoracic dura is reported. Serial magnetic resonance (MR) images detected isolated thickening and ridges of the dura mater. There has been no report describing the serial changes of MR images in idiopathic HSP. According to a review of the English and Japanese literature on idiopathic HSP, the prognosis of patients with positive inflammatory signs is worse than that of those with no inflammatory signs. Idiopathic HSP is a rarely reported disease that can resemble other disorders associated with dural compression. MR imaging can help to differentiate it from other disorders, and enables the diagnosis of the disease in its early stage. The prognosis of idiopathic HSP with positive inflammatory signs may be worse; the authors stress the significance of early surgical treatment.

Dura Mater↗
PubMed1994

Angiocentric lymphoma with granulomatous panniculitis in the skin expressing natural killer cell and large granular T-cell phenotypes.

We investigated three patients suffering from angiocentric lymphoma with granulomatous panniculitis in the skin. All three patients presented with multiple purple subcutaneous nodules. Immunohistologically, the lymphoma cells in all three patients expressed CD2 (T-11), CD56 (neural cell adhesion molecule), and Mik-beta 1 (interleukin-2 beta receptor). CD3s (CD3, Leu-4)-positive lymphoma cells were found in two patients. A pore-forming protein (perforin) was detected in the lymphoma cells of all three patients. Perforin-possessing lymphoid cells were focally scattered in 2 of 15 patients with CD56-negative cutaneous lymphomas who served as controls. By the Southern blot method, one patient showed a rearranged T-cell receptor (TcR)beta gene in the biopsied specimen, and the other two patients had germ-line configurations of TcRs and immunoglobulin heavy chain genes. One patient had serum anti-human T-cell lymphotropic virus (HTLV)-I antibody, but showed no integration of its proviral DNA. Ultrastructurally, membrane-bound azurophilic granules were detected in the atypical lymphoid cells of all three patients. Angiocentric lymphoma with panniculitis in three patients showed the characteristics of natural killer and large granular T-cells. The histological features might be due to the characteristics of the neoplastic cells with azurophilic granules and perforin.

Aged↗
PubMed1994

Quadriplegia caused by push-up exercises.

This paper describes a case of a 52-year-old male patient with spinal cord injury caused by doing push-up exercises in the prone position. To our knowledge, no previous report has been published describing a case of spinal cord injury caused by push-up exercise. These days, sport is recommended not only to the young but also to older persons. However, to the older, who inevitably have some degenerative disease, moderation should be recommended.

Cervical Vertebrae↗
PubMed1994

Accumulation of unintegrated viral DNA in rat glial cells infected with neurotropic Friend murine leukemia virus.

FrC6 virus isolated from Friend murine leukemia virus (FLV) as a neurotropic virus clone induced a high-degree of accumulation of unintegrated viral DNA during infection of rat glial cells by 72 h post-infection. When anti-FLV neutralizing antibody, dextran sulfate, or 3'-azido-3'-deoxythymidine (AZT) was added to the culture within 24 h after infection, the accumulation of unintegrated viral DNA was inhibited. However, after 30-36 h post-infection, addition of anti-FLV antibody or dextran sulfate scarcely inhibited the accumulation of the unintegrated viral DNA, while addition of AZT at 30-36 h post-infection still reduced the amount of unintegrated viral DNA. Our results demonstrate that after 30-36 h post-infection, when second-round infection had already taken place, further superinfection with cell-free virus to glial cells was not required for the accumulation of unintegrated viral DNA. Possible mechanisms are discussed.

Animals↗
PubMed1994

Interaction of Escherichia coli RecA protein with ATP and its analogues.

Interactions of Escherichia coli RecA protein with ATP and its analogues in the absence of DNA were studied by circular dichroic (CD) spectroscopy. The binding of RecA protein to ATP increased the CD band of ATP at around 260 nm. The positive CD band of the RecA protein-ATP complex suggested that the bound ATP was in the anti conformation, in accord with X-ray crystallographic data [Story, R.M. and Steitz, T.A. (1992) Nature 355, 374-376]. At pH 7.5 and at 25 degrees C the dissociation constant (Kd) and thermodynamic parameters for the binding of ATP to RecA protein were 18 microM (delta G = -6.5 kcal.mol-1), delta H = 0 kcal.mol-1, and delta S = 22 cal.mol-1.K-1. A non-hydrolyzable ATP analogue, adenosine 5'-O-(3-thiotriphosphate) (ATP gamma S), gave a spectral change similar to that of ATP. The Kd for this analogue, 22 microM, was very close to the Km of ATP. These results in the absence of single-stranded DNA were different from those obtained by kinetic analysis [Weinstock, G.M. et al. (1981) J. Biol. Chem. 256, 8850-8855], which indicated that the inhibition constant of ATP gamma S was much smaller than the Km of ATP in the presence of DNA. For other ATP analogues (dATP, ADP, and dADP), similar spectral changes were observed, and their Kd values ranged from 19 to 54 microM. UTP, dUTP, and TTP also gave CD spectral changes, but not AMP, GTP, dGTP, CTP, and dCTP.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Triphosphate↗
PubMed1994

Atrial natriuretic peptide reduces cyclic AMP by activating cyclic GMP-stimulated phosphodiesterase in vascular endothelial cells.

Bovine aortic endothelial cells contain cyclic GMP-stimulated phosphodiesterase (PDE) regulating intracellular cyclic AMP and cyclic GMP levels. To investigate the roles of this PDE isoform for cyclic AMP hydrolysis in intact endothelial cells (EC), we used an adenine prelabeling method to determine cyclic AMP accumulation in response to agents that might produce effects that increase cyclic GMP levels. Atrial natriuretic peptide (ANP), which dramatically increased cyclic GMP accumulation, reduced cyclic AMP in cultured EC from bovine aorta with or without addition of L-isoproterenol (L-ISO), whereas sodium nitroprusside (SNP) and 8-bromo cyclic GMP had no effect. The reduction in cyclic AMP by ANP was dose dependent (> or = 1.0 nM) and rapid (significant reduction was induced in < or = 15 s) and was abolished when EC were preincubated with 3-isobutyl-1-methylxanthine (IBMX) and HL-725, both nonselective PDE inhibitors. ANP had no effects on adenylate cyclase activity, nor any direct effects on the activities of partially purified cyclic GMP-stimulated PDE isoform or cyclic AMP-specific isoform. However, cyclic AMP hydrolyzing activities of EC were enhanced when EC were pretreated with 0.1 microM ANP. ANP activates cyclic GMP-stimulated PDE and induces reduction of cyclic AMP accumulation in intact EC, which may modify cyclic GMP-dependent endothelial function involved in ANP.

1-Methyl-3-isobutylxanthine↗