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Biomedical subjects

J Tanaka

Publications and source records attributed to J Tanaka.

At least 721 records · Page 40Linked to original sources

Long survival in Fukuyama congenital muscular dystrophy: occurrence of neurofibrillary tangles in the nucleus basalis of Meynert and locus ceruleus.

Three patients with Fukuyama congenital muscular dystrophy (FCMD), who died aged 23, 29 and 34 years, are reported. There was extensive brain malformation, but the most severe pattern of cortical dysplasia was absent in one case and in the other two localized bilaterally to small areas near the occipital poles. In two cases, numerous neurofibrillary tangles were observed in the locus ceruleus and nucleus basalis of Meynert. Electron microscopy revealed paired helical filaments, with a maximal width of about 25 nm and regular constrictions at approximately 80 nm intervals. The occurrence of neurofibrillary tangles, which is unknown in younger patients, suggests the presence of degenerative processes in the brains of the older patients with FCMD.

Adult↗

Rabbit kidney cells abortively infected with human cytomegalovirus are arrested in mitotic phase.

In rabbit kidney epithelial cells (RK13) abortively infected with human cytomegalovirus (HCMV), DNA synthesis at 1 or 2 days post-infection was enhanced 4 to 5 fold, compared to mock-infected cells. DNA analysis by isopycnic centrifugation revealed that the DNA newly synthesized in the virus infected RK13 cells was of cellular origin. HCMV infection also caused a marked increase in the mitotic activity of RK13 cells. When semi-confluent RK13 cells were infected more than 20 per cent of cells demonstrated mitosis at 72 hours post-infection although the rate of cell growth was considerably reduced compared to that of uninfected cells. The most frequent chromosomal change observed was fragmentation although other aberrations, gap, break, deletion etc. occurred also. Two immediate-early viral polypeptides with apparent molecular weights 72,000 (72K) and 76,000 (76K) daltons were produced in both RK13 cells and human embryonic lung cells (HEL) by 3 hours post-infection. Synthesis of the 76K polypeptide was greater than that of the 72K polypeptide in non-permissive RK13 cells whereas the reverse occurred in permissive HEL cells. Furthermore, of three early polypeptides which were expressed in productively infected HEL cells two, 88K and 80K, were not detected in abortively infected RK13 cells. These results suggest that the arrest in mitosis of the abortively infected RK13 cells and the subsequent chromosomal changes are associated with the altered expression of immediate-early or early virus functions in these cells.

Animals↗

Latent infection of human ovarian teratocarcinoma cells with human cytomegalovirus. Brief report.

Persistent infection with human cytomegalovirus (HCMV) can be established in cultures of human ovarian teratocarcinoma (PA1) cells, and maintained for more than 200 days. Infected cultures maintained at 34 degrees C (PA1CMV34) and 37 degrees C (PA1CMV37) entered crisis and subsequently displayed massive cytopathic effects (CPE), whereas infected cultures maintained at 32 degrees C (PA1CMV32) and 39 degrees C (PA1CMV39) continued to release small amounts of infectious virus until 240 or 151 days post-infection (p.i.) respectively. PA1CMV32 cultures shifted to 37 degrees C at 258 days p.i. resumed synthesis of infectious virus which resulted in cell destruction, indicating that latent infection with HCMV was maintained in PA1 cells at 32 degrees C. In contrast, PA1CMV39 cells did not produce infectious virus even when cultured at 37 degrees C for more than 100 days after the temperature shift.

Bromodeoxyuridine↗

Effect of hepatic artery embolization on the adenylate energy charge level and the redox state of the cirrhotic liver.

Hepatic energy charge ((ATP + 1/2ADP)/(ATP + ADP + AMP)) and arterial blood ketone body ratio (acetoacetate/3-hydroxybutyrate) were measured after hepatic artery embolization in carbon-tetrachloride-induced cirrhotic rats. In normal livers, energy charge slightly decreased at 3 h and returned to normal levels at 6 h. By contrast, in cirrhotic livers, energy charge was drastically decreased at 3 h after embolization and was not completely recovered at 6 h. Blood ketone body ratio, reflecting hepatic mitochondrial redox (NAD+/NADH) state, also decreased at 3 h after embolization in both groups, and its recovery was not observed in cirrhotic group at 6 h.

Adenine Nucleotides↗

Action of the lateral hypothalamic area on subfornical organ neurons projecting to the supraoptic nucleus in the rat.

The activity of all subfornical organ neurons (N = 20) that were antidromically identified by electrical stimulation of the rat hypothalamic supraoptic nucleus region was excited by microiontophoretically applied angiotensin II. Electrical stimulation of the lateral hypothalamic area produced either an excitatory response (N = 12) or no effect (N = 8) in the activity of identified subfornical organ neurons. The excitatory responses to iontophoretically applied angiotensin II or stimulation of the lateral hypothalamic area were blocked by iontophoretically applied saralasin, an antagonist of angiotensin II.

Angiotensin II↗

Subfornical organ efferents influence the activity of median preoptic neurons projecting to the hypothalamic paraventricular nucleus in the rat.

Twelve neurons in the median preoptic nucleus were antidromically activated by electrical stimulation of the hypothalamic paraventricular nucleus in the rat. Electrical stimulation of the subfornical organ produced excitation (N = 7) or inhibition (N = 4) of the activity of these identified units. The activity of all identified units that were excited by stimulation of the subfornical organ was also excited by microiontophoretically applied angiotensin II whereas the remaining units were not affected. The excitatory responses of the identified units to subfornical organ stimulation or applied angiotension II were blocked by saralasin, an angiotensin II antagonist.

Angiotensin II↗

Angiotensin II-sensitive neurons in the rat lateral hypothalamic area with efferent projections to the subfornical organ.

Thirteen neurons in the lateral hypothalamic area were antidromically activated by electrical stimulation of the subfornical organ in the rat. The activity of almost all identified neurons (N = 11) was excited by microiontophoretically applied angiotensin II. On the other hand, of the antidromically unidentified lateral hypothalamic area neurons (N = 10) tested, 4 were excited by microiontophoretically applied angiotension II and 6 were not affected. The excitatory responses of identified and unidentified lateral hypothalamic area neurons to angiotensin II were blocked by microiontophoretically applied saralasin, an angiotensin II antagonist.

Action Potentials↗

Remarkable responses of metastatic renal cell cancer in multiple organs treated with alpha-interferon.

We report a case of renal cell carcinoma with metastases in the lungs, humerus and brain, which we treated with alpha-interferon. After a transperitoneal nephrectomy the patient received a series of intramuscular injections of alpha-interferon every 2 days. Two months after the initial therapy complaints of pain in the humeral bone gradually decreased and the palpable mass in the right brachial region disappeared completely. A computerized tomography scan revealed only the scar of the intracranial metastasis. Most of the pulmonary lesions disappeared 4 months later except for the metastasis at the apex of the left lung.

Adult↗

Combination chemotherapy with cisplatin and peplomycin in squamous cell carcinoma of the head and neck.

Ninety-three patients with head and neck cancer were treated with combined cisplatin-peplomycin chemotherapy (CP therapy). Cisplatin (CDDP) 50 mg/m2 i.v. (intravenous) or i.a. (intraarterial) over 2 hr was given with hydration and mannitol diuresis on day 1. From day 2 through day 6, peplomycin (PEP) 5 mg/day was administered by 5-hr i.v. or i.a. infusion, or 24-hr continuous hypodermic injection. Of 85 who were evaluable, there were 22 complete responses or CR (26%) and 36 partial responses or PR (42%), with an overall response rate of 68%. Concerning of the route of administration, i.a. infusion obtained the higher CR and overall response rates than i.v. infusion. Effectiveness was clearly greater in previously untreated cases than in cases that had received some previous therapeutic modality. Looking at response in relation to the number of the courses, at least 2 courses of CP therapy are required. Side effects were recognized in 68 out of 87 evaluable cases (78%). Nausea and vomiting were the most common (62%). Renal toxicity was observed in 24% and was mostly transient. From the above results, it is considered that the CP therapy is effective, not only for the palliative treatment of advanced and recurrent cancer of the head and neck, but also as neo-adjuvant chemotherapy of stage III and IV cases.

Adult↗

Influence of lesions of the limbic-hypothalamic system on metabolic response of pyruvate to daily repeated immobilization stress in rabbits.

The pyruvate metabolic response to the 1st exposure (exposure on the 1st day) to immobilization stress (IMO) were considerably altered by lesions of the periventricular arcuate nucleus (ARC), ventromedial hypothalamus (VMH), stria terminalis (ST) and dorsal fornix (FX). The pyruvate metabolic responses to IMO were completely abolished by seven times repetition of exposure to IMO in the rabbits with lesions of ARC and VMH; they were similar to sham-operated groups. In rabbits with lesions of ST and FX, the pyruvate metabolic responses to the 7th exposure (exposure on the 7th day) to IMO were almost the same as those after the 1st exposure to IMO, but these metabolic responses were completely abolished by the seven times repetition of exposure to IMO in the sham-operated animals. These results suggest that firstly the ARC, VMH, amygdala (AMYG)-ST system and dorsal hippocampus (HPC)-FX system are involved in the pyruvate metabolic responses to the 1st exposure to IMO, and secondly, that the AMYG-ST system and the HPC-FX system are involved in the disappearance process of pyruvate metabolic responses to IMO by the daily repetition of exposure to IMO.

Animals↗

Isolation and expression in Escherichia coli of a cDNA clone encoding porcine pancreatic elastase.

We have cloned a DNA that is complementary to the messenger RNA that encodes porcine pancreatic elastase 1 from pancreas using rat pancreatic elastase 1 cDNA as a probe. This complementary DNA contains the entire protein coding region of 798 nucleotides which encodes an elastase of 266 amino acids, and 22 and 136 nucleotides of the 5' and 3'-untranslated sequences. When this deduced amino acid sequence was compared with known amino acid sequences, a carboxy-terminal 240 amino acids long peptide was found to be identical with a mature form of porcine pancreatic elastase 1, except for two amino acids. The porcine enzyme contains the same number of amino acid residues as the rat enzyme, and their amino acid sequences are 85% homologous. Taking the above findings together, we conclude that the cloned cDNA encodes a mature enzyme of 240 amino acids including a leader and activation peptide of 26 amino acids. We expressed the cloned porcine pancreatic elastase 1 cDNA in E. coli as a lac-fused protein. The resulting fused protein showed enzymatic activity and immunoreactivity toward anti-elastase serum.

Amino Acid Sequence↗

Human cytomegalovirus persistent infection in a human central nervous system cell line: production of a variant virus with different growth characteristics.

The susceptibility of human central nervous system cell lines to human cytomegalovirus (HCMV) and the fate of infected cultures were studied. Significant amounts of infectious progeny virus were produced in 118MGC glioma and IMR-32 neuroblastoma, but not in KGC oligodendroglioma cells when the cultures were infected with wild-type virus (HCMVwt) at an m.o.i. of 10 p.f.u. per cell. Further passage of infected 118MGC cells resulted in the establishment of a long-term persistent infection. This infection, designated 118MGC/Towne, continuously produced infectious virus (HCMVpi) with titres ranging from 10(2) to 10(5) p.f.u./10(6) cells up to 360 days post-infection (corresponding to 50 subcultures). Since no temperature-sensitive mutants, defective interfering particles or interferon-like activity were found in the 118MGC/Towne cultures, maintenance of the persistent infection seemed to be due to a balance between the release of infectious virus and the growth of uninfected cells. The HCMVpi produced in long-term persistently infected cultures was shown to be different from the HCMVwt originally used to infect by the following characteristics: HCMVpi replicated slowly and yielded lower amounts of progeny virus than HCMVwt; HCMVpi induced a 73,000 mol. wt. immediate early protein that was not synthesized in HCMVwt-infected cells; HCMVpi had a different DNA structure from that of HCMVwt. These results suggest that HCMVpi is a slower growing variant of HCMVwt and probably plays an important role in the maintenance of the persistent infection.

Cell Division↗

Persistent light reaction: induction in the guinea pig.

Persistent light reactions similar to those in humans were observed in the study of photoallergenicity of chemicals in guinea pigs. The animals photoinduced with chemicals reacted to long-wavelength ultraviolet (UVA) radiation in the absence of test materials at the challenge stage. The sensitivity of the animals to UVA persisted for more than 1 year. The minimum erythema dose to UVB of animals in the treated group was less than that in the control group. Our investigations indicate that the main factors influencing the elicitation of persistent light reaction were the amount of Freund's complete adjuvant (FCA) used to enhance the allergic response in animals, and the UVA dose at the induction stage. Based on these findings, we have developed a method to make animals persistent light reactors with high frequency. This method consists of 1 intradermal injection of 1.2 ml emulsified FCA, 5 irradiations with 20.4 J/cm2 of UVA, and topical applications of 5% p-aminoethylbenzoate (benzocaine) at the induction stage. We also found that photosensitivity could be induced using FCA and UVA without photosensitizers.

4-Aminobenzoic Acid↗

Inflammatory activity of a trypsin-like protease in the tuberculin reaction sites in guinea pig skin.

A trypsin-like protease(s) was found in the extracts from tuberculin reaction sites in the guinea pig skin. Extractable enzyme activities were chronologically paralleled with the gross appearance of the inflammation, and the maximum activity from 24-hour old inflamed sites was about 12 times stronger than that from control skin, suggesting a potential role in the pathogenesis of the delayed hypersensitivity reaction (DHR). The enzyme suitably hydrolyzed t-butyloxycarbonyl-phenylalanyl-seryl-arginine 4-methylcoumaryl-7-amide, and was partially purified by gel filtration. It showed an apparent molecular weight of 700,000 with optimal pH of 9.0-9.5. The activity was inhibited by various serine protease inhibitors but not by thiol or metal protease inhibitors. It was relatively heat-stable. These findings suggest that the protease is similar to a trypsin-like protease from DHR to bovine gamma-globulin. Intradermal injection of the enzyme into normal guinea pigs induced a mixed neutrophil-mononuclear infiltrate. The reaction was reduced in intensity with the diisopropylfluorophosphate-inhibited enzyme preparation. The enzyme did not induce any increased vascular permeability. These findings suggest that the protease may be present generally in the DHR sites and probably participates in the cellular response of DHR.

Animals↗

Neurofibromatosis presenting with aqueductal stenosis due to a tumor of the aqueduct: case report.

A 17-year-old boy with neurofibromatosis presented with delayed puberty and epileptic seizures of recent onset. A computed tomographic scan revealed aqueductal stenosis due to a tumor of the aqueduct. This tumor was found at autopsy to be a pilocytic astrocytoma. Aqueductal stenosis in neurofibromatosis is uncommon and has been considered to be a result of periaqueductal gliosis. This seems to be the first report of neurofibromatosis associated with a tumor of the aqueduct.

Adolescent↗

Regulatory effects of gastrin and secretin on carcinomas of the stomach and colon.

Gastrin (10 micrograms/ml) enhanced 14C-leucine uptake in cultured tissue of stomach and colon carcinomas and content of 14C-labelled protein in the medium was increased. One of 2 stomach and one of 3 colon carcinomas transplanted into nude mice were enhanced in growth by pentagastrin injected in a dose of 250 micrograms/kg every day. On the other hand, secretin (100 U/kg) inhibited the trophic action of pentagastrin.

Adenocarcinoma↗