Nucleotide excision repair proteins may be involved in the fixation of glyoxal-induced mutagenesis in Escherichia coli

Earlier studies in our laboratories demonstrated that particles of a number of snack foods that are retained on the dentition accumulate fermentable sugars and short-chain carboxylic acids (SCCA; acetic, formic, lactic, and propionic) to different degrees. The present study was undertaken to test the hypothesis that the accumulated SCCA can induce a gingival inflammatory response. Five periodontally and medically healthy subjects were given portions of plain doughnuts (high SCCA levels) or oatmeal cookie (low SCCA), or had the SCCA applied directly to the gingival margins of designated teeth. Subjects were given wax to chew, or nothing, as controls. Inflammation was assessed by measurements of subgingival temperature, flow rates of gingival crevicular fluid (GCF), and neutrophil emigration into GCF. Subgingival temperatures of the maxillary gingiva rose by 1.32 +/- 0.30 degrees C (mean +/- SE) 5 min after the subjects consumed the doughnuts and remained elevated for at least 1 hr. These values were significantly higher than those obtained from subjects after ingestion of oatmeal cookies (0.63 +/- 0.17 degree C; p < 0.01), consistent with the low levels of SCCA in the retained cookie particles. Wax chewing elicited a similar response, indicating a masticatory effect on the gingiva. Gingival temperatures in the unchallenged controls remained unchanged. Neutrophil emigration into the GCF was significantly elevated in subjects after doughnut consumption. Rinses with a solution of SCCA, or application of the SCCA to the gingiva, also brought about significant elevations in subgingival temperature and neutrophil emigration. The findings describe the inflammatory effects of food ingestion on the gingiva of healthy human subjects, and support the hypothesis that SCCA in the particles of retained food are at least partly responsible for the observed responses.     

Correlation between corrosion rate and AE signal in an acidic environment for mild steel

The AE method is an effective technique for inspecting corrosion damage of mild steel, such as tank bottom floors. However, the correlation between AE signals and corrosion behaviour for mild steel has not yet been fully clarified. In the present study, the authors considered that the corrosion regions of bottom floors become a strong acid environment by Cl⁻, as reported in a previous study. Thus, the polarization resistance for the test pieces of mild steel was measured with an AC impedance method under a strong acid environment. It was clear that the polarization resistance indicated the corrosion rate for a test piece of mild steel in the experiments. While measuring the AE signals, the corrosion rate was monitored with a test piece. As a result, the AE signal showed good correlation with the corrosion rates of the test pieces. The corrosion behaviour of the test pieces was then discussed with the corrosion potential measured during the experiments. Furthermore, the cathode current was changed to control the generated hydrogen gas volume. The volume of the hydrogen gas generated from the cathode reaction was correlated to the AE signals.     

Drug Release Properties of the Microcapsules of Adriamycin Hydrochloride with Ethylcellulose Prepared by a Phase Separation Technique

Adriamycin hydrochloride was microencapsulated with ethylcellulose by a phase separation method to develop a prolonged release dosage form. Polyisobutylene (PIB) was used as a coacervation-inducing agent to control the particle size and drug release rate of the resultant microcapsules. With increasing the concentration of PIB (1 to 3 %) the average diameter of the microcapsules decreased, due to the fact that the microcapsules were discreted to a single microcapsule. At low concentration of PIB, the resultant microcapsules were agglomerated, which resulted in increasing the size. The microcapsules prepared with PIB 2 % prolonged desirably the drug release from the microcapsules. A little size effects of the microcapsules on the drug release rate was found for the microcapsules with PIB 2 % and 3 %.     

Yield enhancement effects of boosted dual word-line (BDWL) schemefor high density DRAMs

This paper describes the yield enhancement effects of a boosted dual word-line (BDWL) scheme for the first Al wiring in high density DRAMs, with a defect density model and a yield model used for comparison with that of the commonly used word-shunt (WS) scheme. Additionally, the yield of first Al wiring with a step height between memory cell array and peripheral circuit regions is also estimated. The yield estimation demonstrated that the yield enhancement effect of the wide first Al wiring for the BDWL scheme was comparable with or surpassed that of the redundancy for the WS scheme yield, when the first Al wiring pitch over the memory cell array or a BDWL scheme was over 4 times wider than that of the WS scheme. The yield estimation with step height indicated that the first Al wiring yield of the BDWL scheme with the step height exceeded that of the WS scheme with the step height of zero, even if using some global planarization technology     

Plasma endotoxin and cytokine concentrations in patients with hemorrhagic shock

OBJECTIVES: The roles of cytokines and endotoxin in hemorrhagic shock, particularly the translocation of endotoxin and bacteria during hemorrhagic shock, were investigated. DESIGN: Prospective study. SETTING: Critical care and emergency center of a university hospital. PATIENTS: Twenty-nine patients with hemorrhagic shock and 20 healthy controls. INTERVENTIONS: Serial blood samples were collected from both study and control patients. Standard resuscitation techniques were used. MEASUREMENTS AND MAIN RESULTS: Plasma levels of endotoxin and various cytokines were determined repeatedly during hemorrhagic shock. Endotoxin was measured using an endotoxin-specific assay in addition to a new perchloric acid method for pretreatment of plasma. Cytokines were measured by commercial enzyme-linked immunosorbent assays. Plasma endotoxin concentrations remained within the normal range for 7 days after admission. Although levels of tumor necrosis factor-alpha and several interleukins increased slightly in some patients, these cytokines did not reach the levels seen in septic shock. CONCLUSIONS: Translocation of bacteria or endotoxin from the gastrointestinal tract into the bloodstream has been noted in animal experiments; however, translocation was not detected in our patients with hemorrhagic shock.     

TX-1877: design, synthesis, and biological activities as a BRM-functional hypoxic cell radiosensitizer

PURPOSE: 2-Nitroimidazole acetamide TX-1877 and its derivatives (TX-1877 analogs) were designed, synthesized, and evaluated by their in vitro and in vivo radiosensitization, tumor growth control, suppression of lung metastasis, and immunopotentiation, as biological response modifier (BRM)-functional hypoxic cell radiosensitizers. MATERIALS AND METHODS: TX-1877 analogs were designed and synthesized in our laboratory. In vitro radiosensitizing ability was estimated using EMT6/KU cells under hypoxic conditions. In vivo radiosensitization, antimetastasis, and immunopotentiation were evaluated using female C3H/He mice bearing the SCCVII tumor. Days (15 or 10) after the inoculation of 10(5) SCCVII tumor cells into the hinder thigh, a drug (0.4 mg/g) was administered i.p. and local irradiation of 30 Gy was given at 30 min after its administration. Tumor growth was observed for 20 days and mice were euthanized to count the number of metastatic nodules on the surface of the lungs. Tumor tissues were extirpated and stained by the ABC method at 1, 2, and 3 weeks after treatment for immunological evaluation. RESULTS: Novel types of bifunctional radiosensitizers, TX-1877 and its analogs possessing BRM-functions (i.e., antimetastatic and immunopotentiation effects) were developed. In vitro radiosensitizing abilities of TX-1877 and its analogs, with their partition coefficient values of more than 0.050, were comparable to misonidazole (MISO) at their doses of 1 mM. Tumor regrowth was suppressed evidently 20 days after the treatment in the irradiated group with TX-1877 (TX-1877 plus R) and with KIN-806 (KIN-806 plus R). The former group reduced markedly the mean number of metastatic lung nodules regardless of radiation therapy. TX-1877 and KIN-806 plus R induced helper T lymphocytes. The TX-1877, TX-1877 plus R, KIN-806, and KIN-806 plus R enhanced macrophage infiltration for 3 weeks after treatment. CONCLUSION: TX-1877 is an excellent BRM-functional hypoxic cell radiosensitizer, expected to be useful for clinical use.     

Retrospective analysis of the treatment of patients with small cell lung cancer showing poor performance status

To assess the feasibility of treatments for patients with small cell lung cancer (SCLC) showing a poor performance status (PS, Eastern Cooperative Oncology Group; ECOG 3 or 4), we retrospectively reviewed the outcome for 13 SCLC patients showing poor PS treated at the National Cancer Center Hospital between January 1984 and May 1994. The main factors which contributed to poor prognosis were superior vena cava (SVC) syndrome, massive pleural effusion, tracheal stenosis due to lymph node swelling, pericardial effusion and pulmonary fibrosis (causing dyspnea in combination), brain metastasis resulting in neurological disturbance, cachexia, Eaton-Lambert syndrome causing muscle weakness, retroperitoneal lymph node metastasis causing abdominal pain, peritoneal effusion due to abdominal lymph node swelling, vertebral metastasis causing paraplegia, and dermatomyositis/polymyositis (DM/PM) causing muscle weakness. All of the patients received chemotherapy with or without radiotherapy. The PS of 8 patients improved with treatment, but no improvement was seen in 5. We analyzed these 13 patients and considered the treatments for those with poor PS. Chemo-radiotherapy was tolerable in SCLC patients showing PS 3, and improved their PS if severe conditions or combined disease did not arise concurrently. It was further suggested that PS 4 patients with severe conditions or combined disease should not be given the treatments.     

Asymptomatic hyponatremia due to inappropriate secretion of antidiuretic hormone as the first sign of a small cell lung cancer in an elderly man

A 72-year-old man was hospitalized with asymptomatic hyponatremia. Despite hyponatremia, urinary sodium excretion with urine osmolality exceeding plasma osmolality persisted. Plasma vasopressin levels were high and independent of plasma osmolality during hypertonic saline infusion. Computed tomography of the chest showed enlarged mediastinal and right hilar lymph nodes. Microscopically, a specimen of lymph nodes obtained by biopsy represented vasopressin-producing small cell lung carcinoma. Chemotherapy plus irradiation improved the hyponatremia. Thus, careful evaluation is necessary to determine the cause of hyponatremia disorders in elderly patients.     

FORMATION OF MULLITE FROM GROUND PRODUCT OF A KAOLINITE-ALUMINUM TRIHYDROXIDE MIXTURE BY SOLID PHASE REACTION

The present paper describes the effect of grinding a kaolinite/aiuminum-trihydroxide mixture using a planetary ball mill on the structure of the ground product and the mean thermal expansion coefficients of samples sintered from the unground and ground mixtures. The size reduction of the mixture predominates in the early stage of grinding and the obtained fine particles aggregate subsequently with an increase in grinding time. The crystal structure of the mixture is collapsed easily into a disordered one, of which amount increases with an increase in grinding time. Only mullite phase was detected in the sintered body of the ground products at relatively lower temperature 1523K except for anatase as an inherent impurity, whereas corundum, cristobalite and Al-Si spinel phases besides mullite were formed in the sintered body of the unground mixture. The thermal expansion coefficients of sintered bodies of the 120 minutes-ground mixture are considerably lower than those of the unground mixture by about 10%. Consequently, the planetary milling enables us to improve the uniform mixing state at the atomic scale resulting in direct formation of mullite with high purity at relatively low temperature with a lower thermal expansion coefficient of the sintered body.     

Enzymatic activity and expression of cytochrome P450 LA omega within intrasplenically transplanted fetal hepatocytes in spontaneously hypertensive rats

We examined the expression and enzymatic activity of cytochrome P450 LA omega within transplanted hepatocytes. Fetal hepatocytes were harvested at day 20 of gestation from spontaneously hypertensive rats (SHRs) and transplanted into recipient adult SHR spleens. Microscopic examination of the recipient spleens at 4 and 10 wk after transplantation revealed masses of hepatocytes with cord-like structures in the red pulp. Immunochemical studies detected cytochrome (cyto) P450 LA omega in the fetal hepatocytes before transplantation without prior induction. Although the cyto P450 LA omega was not detected by the second week after transplantation, by the 6th and 10th wk after transplantation, it was. Cyto P450-arachidonic acid omega/omega-1 hydroxylase activity (formation of 20- and 19-hydroxyeicosatetraenoic acid) was detected at 10 wk after transplantation, but not 2 or 6 wk after transplantation. These results demonstrated that fetal hepatocytes can be transplanted successfully into recipient spleens and then grow in the spleens, as in the case of the adult hepatocyte response.