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The objective of this study was to investigate the therapeutic results of arterial injection therapy via the superficial temporal artery for 134 cases of stages III and IV (M0) oral cavity cancer retrospectively, and to clarify the prognostic factors. We administered intra-arterial chemoradiotherapy by continuous infusion of carboplatin in 65 cases from January 1993 to July 2002. Systemic chemotherapy was performed on 26 cases at the same time. We administered intra-arterial chemoradiotherapy by cisplatin with sodium thiosulphate in 69 cases from October 2002 to December 2006. Systemic chemotherapy was performed on 48 cases at the same time. The 3-year local control rate was 68.6% (T2-3: 77.9%; T4: 51.3%), and the 3-year survival rate was 53.9% (stage III: 62.9%; stage IV: 45.3%). Regarding the results of multivariate analysis of survival rates, age (<65), selective intra-arterial infusion, and the use of cisplatin as an agent for intra-arterial infusion were significant factors. The therapeutic results of intra-arterial chemoradiotherapy via the superficial temporal artery were not inferior to the results of surgery. In particular, the results of arterial injection therapy by cisplatin with sodium thiosulphate were excellent, so we believe that it will be a new therapy for advanced oral cavity cancer. [ABSTRACT FROM AUTHOR]

We have studied the effect of shear stress on thin films of Pt(dpg)2 and chromic compounds, spiropyrans, by using the sapphire-anvil cell. From Raman spectra under hydrostatic pressure and shear deformation, the shear stress effect on Pt(dpg)2 was quantitatively estimated. Then, it was observed that the color of spiropyran (1′,3′-dihydro-1′,3′,3′-trimethyl-6-nitro-spiro [2H-1-benzopyran-2,2′-[2H]indole]) was changed by shear stress. [ABSTRACT FROM AUTHOR]

A seroepidemiologic, nested case-control study was conducted to evaluate the risk for atrophic gastritis associated with Helicobacter pylori infection. Atrophic gastritis was diagnosed on the basis of serum pepsinogen levels: pepsinogen I level < or = 70 ng/ml and pepsinogen I/pepsinogen II ratio < or = 3.0. Cases were 23 men and 39 women who were not diagnosed with atrophic gastritis in 1987, but who were diagnosed with the condition in 1992. Controls were the 120 men and 282 women who did not meet the serologic criteria for atrophic gastritis in either time period. Neither cases nor controls had a history of upper gastrointestinal operations. Helicobacter pylori infection at the initial survey was associated with a significantly increased risk of atrophic gastritis incidence for both sexes combined (odds ratio = 3.72; 95% confidence interval, 1.78-7.79; P = 0.0005). Cigarette smoking and consumption of alcohol and green-yellow vegetables were not associated with incidence of atrophic gastritis. [ABSTRACT FROM AUTHOR]

Many colorectal cancer cells are resistant to the anti-proliferative effects of transforming growth factor-β (TGF-β). TGF-β also acts as paracrine factor from cancer cells on their mesenchymal cells. The aim of this study was to examine the expression of TGF-β and its receptors in human colorectal cancer tissue and determine any relationship with cancer growth. In situ hybridization and Northern blot hybridization detection of TGF-β[SUB1], type I and type II receptor mRNA and immunohistochemical staining of TGF-β[SUB1] were performed using 11 human colorectal adenomas, 22 colorectal cancers and ten normal colorectal mucosas as control. TGF-β receptor mRNAs were expressed mainly by normal colorectal epithelial cells and adenoma. However, mRNAs for TGF-β receptors were only faintly, if at all, expressed in eight of 22 human colorectal cancers. In addition, intense signals of TGF-β[SUB1] mRNA and the protein were detected in all colorectal cancers. TGF-β receptor mRNAs and TGF-β[SUB1] protein were also distributed in fibroblasts and endothelial cells in the interstitium. Moreover, Smad 4 protein was translocated to nucleus in primarily cultured adenoma cells, but not in cancer cells after TGF-β stimulation. The escape of human colon cancer from TGF-β -mediated growth inhibition by down-regulation of TGF-β receptors as well as the effects of TGF-β on stroma formation and angiogenesis indicate a possible role for TGF-β in the progression of colon cancer in an intact host. [ABSTRACT FROM AUTHOR]

Protoporphyrinogen oxidase, the penultimate enzyme involved in the biosynthetic pathway for heme, catalyzes the removal of six electrons from protoporphyrinogen IX to generate protoporphyrin IX. In Escherichia coli, this enzyme is encoded by the hemG gene. In this study we examined possible alternate pathways for the oxidation of protoporphyrinogen IX to protoporphyrin IX, by isolating and investigating E. coli mutants that can still grow normally when the hemG gene is disrupted. One of these mutants was characterized in detail and had a mutation in the promoter region of the hemF gene, which encodes aerobic coproporphyrinogen oxidase, the enzyme involved in the step immediately before protoporphyrinogen oxidase. Measurement of the promoter activity of the hemF gene showed that the level of transcription was elevated by the mutation. Overexpression of a wild-type hemF gene cloned in a multicopy plasmid also restored the growth of Δ hemG strain. Extracts from cells that overexpress hemF exhibited an increased ability to oxidize protoporphyrinogen IX to protoporphyrin IX. These findings suggest that the E. coli aerobic coproporphyrinogen oxidase has an intrinsic capacity to oxidize not only coproporphyrinogen III but also protoporphyrinogen IX. [ABSTRACT FROM AUTHOR]

A total of sixteen spontaneously generated, independent suppressor mutants was isolated from a mutant ( divE42) of Escherichia coli K12 that is defective in cell division. One of the suppressor mutants, designated TR4, had a novel phenotype: it was able to grow at 42° C but not at 32° C. The Kohara genomic library was screened for complementing clones. Clone 148 was able to complement the mutation responsible for the cold-sensitive phenotype, and the gene for trigger factor ( tig), which encodes a ribosome-associated peptidyl-prolyl cis/ trans isomerase, was identified as the mutated gene by deletion analysis with the insert DNA from clone 148. DNA sequencing revealed that the mutation in the tig gene of the TR4 suppressor mutant was a single nucleotide insertion (+A) at a distance of 834 nucleotides from the initiation codon for this enzyme. When the wild-type tig gene was introduced into the TR4 suppressor mutant, the bacteria were able to grow at 32° C but not at 42° C, an indication that the intergenic suppressor mutation was recessive to the wild-type allele. A model is proposed that accounts for the phenotypes of the divE42 mutant and the TR4 suppressor mutant. [ABSTRACT FROM AUTHOR]

We conducted a seroepidemiological nested case-control study to determine the association of gastric cancer with Helicobacter pylori infection and atrophic gastritis. A cohort of 2858 participants in an annual multiphasic health check-up were followed for eight years. Data for 45 gastric cancer cases and 225 sex-, age-, and address-matched control subjects were analyzed. Helicobacter pylori infection was determined by IgG antibodies, and atrophic gastritis was diagnosed by both serum pepsinogen I level (< or = 70 ng/ml) and the pepsinogen I/II ratio (< or = 3.0). Univariate analysis showed that Helicobacter pylori and atrophic gastritis were significantly associated with gastric cancer. In a multivariate analysis, atrophic gastritis was associated with significantly increased risk of cancer (odds ratio, 3.38; 95% confidence interval, 1.54-7.42); however, Helicobacter pylori was not associated with cancer (odds ratio, 1.84; 95% confidence interval, 0.59-5.72). These results suggest that Helicobacter pylori infection alone is not directly associated with gastric carcinogenesis but has an indirect relation to gastric cancer through the development of atrophic gastritis. [ABSTRACT FROM AUTHOR]

Selective immunohistochemical identification of enterochromaffin (EC) cells in the human duodenum and colon has been carried out, using a highly specific rabbit antiserotonin serum and the unlabeled peroxidase-antiperoxidase complex (PAP) technique. The sensitivity of the reaction, and morphology of the cells, were compared with those of the argentaffin or argyrophil reactions on the same sections at the light microscopic level. All argentaffin cells were argyrophil and PAP positive, but a small number of PAP-positive cells were neither argentaffin nor argyrophil. In addition, a few EC cells stained by the PAP method were shown to be argyrophil but not argentaffin. The PAP method permitted the clear morphological identification of the entire cell, particularly its cytoplasmic processes, whereas both the argentaffin and argyrophil reactions were basically seen in the basal regions of the cells and often failed to demonstrate the cytoplasmic processes. These findings indicate that the immunohistochemical method is more sensitive and advantageous than silver impregnations for the selective demonstration of EC cells. [ABSTRACT FROM AUTHOR]

Selective immunohistochemical demonstration of enterochromaffin (EC) cells in the rat gastrointestinal tract has been carried out, using a highly specific rabbit antiserotonin (5-HT) serum and the unlabeled peroxidase-antiperoxidase complex (PAP), technique. The daily profile of the EC cell density was also studied using this method. No significant change was recorded. [ABSTRACT FROM AUTHOR]

The effects of catechol on membrane properties in lumbar sympathetic postganglionic neurones isolated from guinea-pigs were studied in vitro in current and voltage clamp using single intracellular microelectrodes. Neurones with properties characteristic of two previously described classes of neurone (phasic and tonic) were studied. Catechol (3-12mM) produced a few mV depolarization and a dose-dependent increase in membrane resistance which were both larger in tonic than in phasic neurones. In the presence of catechol, both phasic and tonic neurones fired only a single action potential at the beginning of a maintained depolarizing current step. In both neurone types, catechol reduced action potential amplitude and slowed its time course. The peak of the afterhyperpolarization became delayed and reduced in amplitude, particularly in tonic neurones. The time constant of inactivation of IA was reduced by catechol without change in the voltage sensitivity of activation or inactivation; IC50 was 3mM in phasic and 4mM in tonic neurones. Catechol also blocked a slow voltage-activated K+ current (resembling ID) that was present in many tonic neurones. Catechol did not modify the slow calcium-activated potassium current (gKCa1) or the anomalous rectifier; neither did it appear to affect the fast calcium-activated potassium current (IC) or the delayed rectifier. Catechol did not change the overall rate of spontaneous synaptic activity nor enhance the release of quanta of ACh from preganglionic terminals evoked by nerve stimulation. We conclude that, in addition to blocking IA, catechol blocks the slow ID-like current in sympathetic neurones. It also has a profound effect on the action potential probably by increasing inactivation of voltage-dependent Na+ channels. The change from tonic to phasic discharge in tonic neurones cannot be attributed solely to its effects on IA. [ABSTRACT FROM AUTHOR]

A study is described of the regulation of porphyrin synthesis in Escherichia coli using a heme-permeable, hemH deletion mutant, designated VS212. This strain utilizes only exogenous hemin that is supplied in the medium and accumulates porphyrins since the final step in the synthesis of heme is genetically blocked. It is possible, therefore, to monitor the rate of synthesis of heme by examining the accumulation of porphyrins. Using this system, we found that the rate of production of porphyrins depended on the availability of heme. The lower the concentration of hemin in the medium, the higher the level of porphyrins that accumulated. We next examined the mechanism responsible for the activation of porphyrin synthesis upon starvation for heme. The main activation occurred at the step that leads to the synthesis of 5-aminolevulinic acid (ALA). Starvation for heme induced the expression of a hemA- lacZ fusion gene, as previously reported, but an activation pathway that is independent of the hemA promoter was also identified. We found that starvation for heme caused the stringent response, and such starvation promoted the synthesis of porphyrins without having any effect on the expression of the hemA- lacZ fusion gene. We suggest a model for the regulation of porphyrin synthesis whereby the synthesis of porphyrins is coordinated with that of proteins. [ABSTRACT FROM AUTHOR]

Modulation of angiogenesis is now a recognized strategy for the prevention of various angiogenesis-mediated disorders. We investigated, using well-characterized in vitro systems, the anti-angiogenic property of vitamin E compounds, with particular emphasis on tocotrienol, a natural analog of tocopherol. Tocotrienol, but not tocopherol, inhibited the proliferation of bovine aortic endothelial cells in dose dependent manner at half-maximal concentrations in the low micromolar range. Tocotrienol also significantly inhibited the formation of networks of elongated endothelial cells within 3D collagen gels. From these results, we suggest that tocotrienol is a potential candidate for the development of useful therapeutic agents or preventive food factors for tumor angiogenesis. [ABSTRACT FROM AUTHOR]

The morphology of enterochromaffin (EC) cells in the human fundic mucosa was investigated at the lightmicroscopic level by means of the unlabeled peroxidase anti-peroxidase method, with the use of a highly specific anti-serotonin serum. EC-cells in the human fundic mucosa were sparsely distributed below the neck portion of the gland, but were found to be rather numerous in its lower half. Immunohistochemistry revealed marked pleomorphic and seemingly polynuclear EC-cells or cells with long, sometimes multipolar cytoplasmic processes. In addition, luminal contacts and contiguity between EC-cells, or interglandular connections were also encountered. The present immunohistochemical procedure permits, for the first time, a clear-cut morphological visualization of the entire population of EC-cells, and reveals the distinctive morphological features of these cells in the human fundic mucosa. These morphological findings imply that EC-cells in the fundic mucosa may be crucial in gastric function. [ABSTRACT FROM AUTHOR]

Radioautographic studies of rat duodenal mucosa were carried out after single injections of H-thymidine, and the labelling indices of enterochromaffin (EC) cells identified by serotonin immunohistochemistry and by the diazo reaction were compared. The labelling index of EC cells by serotonin immunohistochemistry was 2.3% (mean percentage of 2 rats), while no labelled cells were found in diazo-positive EC cells. This finding indicates that serotonin immunohistochemistry reveals a less mature population of EC cells than conventional techniques such as the diazo reaction. [ABSTRACT FROM AUTHOR]