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T Todo

Publications and source records attributed to T Todo.

At least 91 records · Page 5Linked to original sources
PubMed1991

Immunohistochemical demonstration of protein kinase C isozymes in human brain tumors.

Immunohistochemical studies of the expression of protein kinase C isozymes were done in 38 human brain tumors using monoclonal antibodies to three major isozymes: Type I, Type II, and Type III. The brain tumors, with the exception of 3 medulloblastomas and 2 of 6 pituitary adenomas, showed strong immunoreactivity for the Type III isozyme. Astrocytomas, anaplastic astrocytomas, and glioblastomas also showed weak immunostaining for Type II, whereas other tumors lacked this staining. Immunoreactivity for Type I was present, although weak, in some astrocytic gliomas. There was no correlation between the presence of immunoreactivity for protein kinase C isozymes or the intensity of staining for the Type III isozyme and the pathological grade of malignancy. In normal human brain tissue, Type I is localized mainly in neuronal cells, Type II in the neuropil of the cerebral cortex and the molecular and granular layers of the cerebellum, and Type III almost exclusively in astrocytes. The presence of immunoreactivity for the Type III isozyme in varying tumor cells, including those of non-astrocytic tumors and the presence of the Type II and/or Type I isozymes in astrocytic gliomas demonstrate that the expression of protein kinase C isozymes differs between normal and transformed cells.

Antibodies, Monoclonal↗
PubMed1991

Sudden appearance of a mycotic aneurysm of the intracavernous carotid artery after symptoms resembling cluster headache: case report.

Acute cavernous sinus syndrome developed in a 44-year-old man after he had experienced symptoms resembling cluster headache for 3 weeks. The cause was determined to be the sudden appearance of a large saccular aneurysm of the intracavernous portion of the left carotid artery secondary to an acute inflammation of the left cavernous sinus. The absence of this aneurysm before the onset of the ophthalmoplegia was confirmed by a computed tomographic scan and angiogram performed only 1 week earlier. The patient was treated with antibiotics in combination with a short regimen of steroids, which resulted in a slowly developing thrombosis of the aneurysm, although the cavernous sinus syndrome remained. This case suggests several important aspects regarding the pathogenesis of mycotic intracavernous carotid aneurysms, the mechanism of an acute manifestation of the cavernous sinus syndrome by an intracavernous carotid aneurysm, and the relation of the intracavernous portion of the carotid artery to cluster headache.

Adult↗
PubMed1991

Treatment of severe intraventricular hemorrhage by intraventricular infusion of urokinase.

Six patients with severe intraventricular hemorrhage were treated with direct intraventricular infusion of urokinase. In each case, hemorrhage extended into all ventricular chambers, and a cast formation and expansion of the third and fourth ventricles were found. Immediately after the therapy was started (within 7 days from onset of symptoms), reduction of intraventricular hematoma volume was observed on computerized tomography. On average, both the third and fourth ventricles became clear on the third day after hemorrhage; there was one exception, a case of ruptured aneurysm. Five of the six patients showed excellent or good outcome, although two developed delayed hydrocephalus. No infection or rebleeding was observed. The outcome in a retrospectively studied group of five patients not treated with urokinase is also reported. The authors conclude that this relatively easy method of treatment will greatly improve the prognosis of severe intraventricular hemorrhage.

Adolescent↗
PubMed1991

Large cysts of the pineal gland: report of two cases.

Two cases of large, nontumorous cysts of the pineal gland are reported, the histopathology of which was confirmed using surgically resected specimens. Both patients were middle-aged, and the pineal cysts were found incidentally. The histopathological findings in the two cases were strikingly similar to each other and were characterized by the following points: 1) the cyst wall typically consisted of three layers, namely, collagenous fibers, glia-like cells, and normal pineal cells; 2) the cyst wall was relatively thin, approximately 100 to 300 microns in thickness; and 3) deposits of calcification almost always existed on the side of the layer of collagenous fiber. Because these findings are clearly different from those previously reported, large benign cysts of the pineal gland, or at least some of them, may constitute a new pathological entity. It is important to consider this possible pathological diagnosis when dealing with pineal cysts.

Adult↗
PubMed1990

Astrocytic localization of the immunoreactivity for protein kinase C isozyme (type III) in human brain.

The localization of 3 major types of protein kinase C (PKC) was immunohistochemically studied in human brain using monoclonal antibodies raised against each of the types. Immunoreactivity for type I was observed in neuronal cells in cerebrum and Purkinje cells in cerebellum. Immunoreactivity for type II was mainly observed in neuropil of cerebral cortex and in the molecular and granular layers of cerebellum. Occasional neurons in cerebrum were also stained. Immunoreactivity for type III was almost exclusively localized in astrocytes in gray and white matter, subpial astrocytes, and cerebellar Bergmann's glia. The present study suggests that the type III of PKC is preferentially expressed in astrocytes in human brain.

Antibodies, Monoclonal↗
PubMed1990

Cooperative enhancement at the Drosophila Sgs-3 locus.

The Drosophila glue gene Sgs-3 is specifically expressed in the secretory cells of the salivary glands of third instar larvae. We have assayed the expression of gene fusions to determine the role of cis-acting Sgs-3 sequences in conferring this pattern of expression. These experiments define two regulatory regions required for expression of reporter genes from the Sgs-3 promoter. One region, between 106 and 56 bp upstream of the Sgs-3 mRNA 5' end is sufficient for low but correct tissue- and stage-specific expression. A second region, lying between 629 and 130 bp 5' of the RNA start site is functionally equivalent; that is, it alone will also direct low level, specific expression. These two regions act synergistically to give high level expression. More distant upstream regions function to further increase levels of expression. These two regulatory elements can confer a salivary gland-specific pattern of expression on a heterologous promoter and are also sufficient to drive gene expression in other Drosophila species, implying conservation of regulators.

Animals↗
PubMed1990

Fine-structure mutational analysis of a stage- and tissue-specific promoter element of the Drosophila glue gene Sgs-3.

The Sgs-3 gene of Drosophila melanogaster exhibits a tightly regulated pattern of expression governed by two functionally equivalent elements within 1 kb of the gene, each of which is sufficient to confer third-instar salivary gland-specific transcription. In this report we describe a detailed functional analysis of one of these, the proximal element. To determine the nucleotides responsible for specific expression, we have introduced mutations into the proximal element and then assessed the effects of each alteration on expression in the developing animal. We have identified six particularly important base pairs which are located in two regions separated by nonessential sequences. These base pairs, along with some surrounding sequence, are conserved within the upstream regions of the three glue genes at 68C. Nearly identical groups of base pairs can be found upstream of the other glue genes which have been cloned. This analysis has allowed us to derive a consensus sequence, which we believe contains binding sites for two different factors which interact to direct third-instar salivary gland-specific expression.

Animals↗
PubMed1988

[Metastatic hepatoma presenting as intracranial hemorrhage: report of two cases].

Metastasis of hepatoma to the central nervous system is rare, although hepatoma is a relatively common malignant tumor in Japan. Much rarer is metastatic hepatoma presenting as intracranial hemorrhage and there have been only 4 cases reported in the past. Here, we report two such rare cases with a literature review. Case 1 was a 26 years-old female with a history of 60% hepatic resection in the diagnosis of hepatocellular carcinoma. Later, she developed bilateral lung metastasis. She was admitted with complaints of headache, nausea and vomiting. Neurological findings were clear consciousness, right homonymous hemianopsia and bilateral papilledema. CT showed high-density mass in the left occipital lobe. Evacuation of hematoma and removal of tumor were performed. Pathological diagnosis was hepatocellular carcinoma of clear cell type. Later, two other hemorrhage occurred from different metastatic lesions in the left occipital lobe and the right occipital lobe, and the patient underwent two more surgeries. The patient died of lung metastasis, three months from neurological onset. Case 2 was a 42 years-old male who developed an intracranial tumor adjacent to the right temporal bone without a history of hepatoma. The tumor was removed, which turned out to be hepatocellular carcinoma pathologically. Three months later, on admission, the patient showed sudden neurological deterioration into deep coma. CT showed an irregular high-density mass in the right temporal lobe and evacuation of hematoma coupled with tumor removal was performed. Pathology was of trabecular type. Later, intracranial recurrence and bony metastasis to C5, L3 and the left iliac bone appeared.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Genetic-molecular basis for a simple Drosophila melanogaster somatic system that detects environmental mutagens.

We have developed a simple, objectively scorable test for the mutagenicity of chemical compounds which can be fed Drosophila melanogaster. The test depends upon the somatic reversion of the X chromosome, recessive eye color mutation, white-ivory (wi) to wild type (w+). Reversions are scored as clones of w+ facets in the wi eyes of eclosing adults. To increase the sensitivity, a tandem quadruplication containing four wi mutations was synthesized. Thus, in homozygous females eight wi mutations are potentially revertible. Six mutagenic compounds, all alkylating agents, all gave positive results at several concentrations tested. Molecular analysis demonstrates that the induced reversions, germinal and somatic, are associated with the loss of 2.9-kilobase DNA duplicated in the wi mutation.

Animals↗
PubMed1985

Structures of defective P transposable elements prevalent in natural Q and Q-derived M strains of Drosophila melanogaster.

Several DNA sequences with homology to the complete 2.9-kilobase (kb) P element from a P strain in the United States were isolated and characterized from two Drosophila melanogaster strains collected on Chichi Jima, an island 1000 km south of Tokyo. Except for a missing central region and trivial unsequenced regions of 38 base pairs, the 2.1-kb element isolated from a Q strain had the same DNA sequence as that of the complete P element. Seven other elements cloned from genomic DNAs of the Q strain and a Q-derived M strain all possessed the same restriction sites as those of the 2.9-kb P element except for one deleted region in each element. The finding of sequence conservation in P elements have had a common ancestor relatively recently. Thus, it is suggested that the P element family was a recent invader of the species. By contrast, no complete P element was found in these Japanese strains so far as surveyed, indicating the possibility that P elements in the Chichi Jima population are almost all defective. The implication of this possibility is discussed in relation to the uniqueness of the population on Chichi Jima where Q strains predominate and no P strains have yet been found.

Journal Article↗
PubMed1985

Mutagenic potency of heterocyclic amines in the Drosophila wing spot test and its correlation to carcinogenic potency.

The Drosophila wing spot test is fast and sensitive for detecting somatic mutation and recombination. Nine heterocyclic amines, which had been identified as mutagenic constituents of cooked food by using the Salmonella/mammalian-microsome test system, were orally fed to larvae of the tester strain. All the compounds (Trp-P-1, Trp-P-2, Glu-P-1, Glu-P-2, IQ, MeIQ, MeIQx, AaC, MeAaC) showed mutagenicity in this system. The reported values of carcinogenic potency in the mouse assay for seven of the nine compounds showed an excellent correlation with mutagenic potency values obtained in the Drosophila assay, but not with those obtained in the Salmonella assay, indicating that the Drosophila short-term test is promising for quantitative pre-screening of potential carcinogens.

Amines↗
PubMed1983

The modulating influence of the fluidity of cell membrane on excision repair of DNA in UV-irradiated Escherichia coli.

When the extent of liquid holding recovery (LHR) was measured as a function of the temperature at the time of liquid holding and the Arrhenius plot was made, two distinctive phases for the LHR were demonstrated in UV-irradiated RecA- derivative of E. coli ole28E1, which are unable to synthesize and degrade unsaturated fatty acids. The inflection temperatures were 17-18 degrees C, 23-24 degrees C and 28-30 degrees C for linoleate-, oleate- and elaidate-grown cells, respectively. These temperatures well corresponded to the phase transition temperatures of the cell membrane supplemented with the fatty acid. It is therefore concluded that at least a component involved in in vivo excision repair in E. coli is associated with cell membrane.

Cell Membrane↗
PubMed1983

Transabdominal oesophageal transection for oesophageal varices: experience in 101 patients.

The results of transabdominal oesophageal transection in 101 patients with oesophageal varices are reported. The primary diagnosis was liver cirrhosis and 65 patients, idiopathic portal hypertension in 29 and extrahepatic portal obstruction in 7. Twelve patients died postoperatively. The mortality rate for emergency operations was higher than that for elective and prophylactic procedures. The majority of patients died from hepatic failure. Improvement, judged by radiographic and endoscopic examination, was 100 per cent and 96 per cent, respectively. Post-transection rebleeding was observed in 14 of 89 patients during the follow-up period of 1-13 years. There were 25 late deaths, caused mainly by hepatic failure. The 5-year survival rate, including postoperative deaths, was 72 per cent in idiopathic portal hypertension and 55 per cent in liver cirrhosis. We suggest that transabdominal oesophageal transection is an acceptable operative procedure for oesophageal varices.

Adolescent↗
PubMed1983

Inhibitory effect of membrane-binding drugs on excision repair of DNA damage in UV-irradiated Escherichia coli.

The effects of procaine and lidocaine on DNA-repair processes were investigated in UV-irradiated cells of E. coli with different DNA-repair capacities. The cells were irradiated with various doses of UV and then incubated at 37 degrees C in M9 buffer (liquid-holding) or in EM9 medium in the presence or absence of membrane-binding drugs. The results obtained are as follows. (1) In strains H/r30 (wild-type for DNA repair) and NG30 (recA-), the increase in survival with increase in time of liquid-holding was almost completely inhibited by the addition of procaine and lidocaine. The same trends were observable under conditions of post-irradiation incubation in EM9 medium, more efficiently in recA- strain than in the wild-type strain. (2) The addition of these drugs gave an apparent enhancement of the frequency of UV-induced mutation to arginine prototrophy, corresponding to a decrease in survival. (3) There were negligible effects of the drugs on survival and mutation in the excision-repair-defective strain, Hs30 (uvrB-). (4) The removal of thymine dimers from DNA was actually reduced by the addition of procaine. From these results it is concluded that procaine and lidocaine inhibited excision-repair process in UV-irradiated E. coli cells. Procaine and lidocaine are typical local anesthetics and known to interact with cell membranes causing alterations in the structural and functional organization. Therefore, it is suggested that a disorganization of the membrane structure brought about by the drugs may result in an inhibition of excision repair of DNA damage in E. coli, assuming that at least a component of excision repair is associated with the cell membrane. Possible mechanisms involved in this process are discussed.

Cell Membrane↗