The Hall effect has been measured for ultrafine particle films of tin oxide (particle size 50–200 Å) in contact with reducing gases. Both the carrier concentration and mobility increased with an increasing concentration of reducing gas. As a result, conductivity, the product of the carrier concentration and mobility, shows a large gas concentration dependence. This means the ultrafine particle films are highly sensitive to gases. The variation of the carrier mobility with the gas concentration is interpreted in terms of a model in which the width of a long, thin channel, determined by particle size and Debye length, increases with a decrease in the number of O− ions desorbed by a chemical reaction with the reducing gases.

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Lymphangiogenesis in oral SCC varies depending on the region within the tumor tissue. It is not induced in the genuine tumor stroma near the invasion front, probably due to the down-regulation of VEGF-C expression of tumor cells, which is different from VEGF-mediated induction of intratumoral angiogenesis.

Abstract.Metastasis is the main cause of cancer-associated death, and metastasis of pancreatic cancer remains difficult to treat because of its aggressiveness. MicroRNAs (miRNAs) play crucial roles in the regulation of various human transcripts, and many miRNAs have been reported to correlate with cancer metastasis. We identified an anti-metastatic miRNA, miR-5100, by investigating differences in miRNA profiling between highly metastatic pancreatic cancer cells and their parental cells. Overexpression of miR-5100 inhibited colony formation (P<0.05), cell migration (P<0.0001) and invasion (P<0.0001) of pancreatic cancer cells. In addition, we identified a possible target of miR-5100, podocalyxin-like 1 (PODXL), and demonstrated miR-5100 directly binds to the 3' untranslated region of PODXL and post-transcriptionally regulates its expression in pancreatic cancer cells. Silencing PODXL resulted in diminished cell migration (P<0.0001) and invasion (P<0.05). We also clarified the close relationship between expression of PODXL in human pancreatic cancer specimens and liver metastasis (P= 0.0003), and determined that post-operative survival was longer in the low-PODXL expression group than in the high-PODXL expression group (P<0.05). These results indicate that miR-5100 and PODXL have considerable therapeutic potential for anti-metastatic therapy and could be potential indicators for cancer metastases in patients with pancreatic cancer.

Background The systemic inflammatory response and nutritional status of patients with malignant tumors are related to postoperative results. We examined the usefulness of the prognostic nutritional index (PNI) as a prognostic tool in patients with oral squamous cell carcinoma who underwent radical surgery. Methods From 2008 to 2019, 102 patients (73 males, 29 females; age, 65.6 ± 9.8 years) who visited our hospital and underwent surgical therapy were included in this study. The endpoint was the total survival period, and the evaluation markers included the lymphocyte count and albumin level in peripheral blood obtained 4 weeks preoperatively, age, sex, alcohol consumption, smoking history, site of the tumor, pathological stage, and surgery status. The PNI was calculated using serum albumin levels and the peripheral blood lymphocyte count. The relationship between the PNI and patient characteristics were analyzed using Fisher's exact test. The Kaplan–Meier method was used to evaluate the survival rate. The survival periods were compared using the log-rank method. We evaluated the prognostic factors for overall survival (OS) and disease-free survival (DFS) in a logistic regression model. Results The tumor sites included the maxilla (n = 12), buccal mucosa (n = 11), mandible (n = 17), floor of the mouth (n = 9), and tongue (n = 53). The number of patients with stage I, II, III, and IV oral cancers was 28 (27.5%), 34 (27.5%), 26 (33.3%), and 14 (13.7%), respectively. During the observation period, 21 patients died of head and neck cancer. The optimal cut-off PNI value was 42.9, according to the receiver operating characteristic analysis. The proportion of patients with a short OS was lower in those with PNI higher than 42.9, and the 5-year OS in patients with PNI higher and lower than the cut-off value was 62.3% and 86.0%, respectively (P = 0.0105). Conclusions The OS of patients with PNI < 42.9 was lower than that of patients with PNI ≥ 42.9. The PNI, which is a preoperative head-to-foot inflammatory marker, can help in estimating the prognosis of oral cancer.

Objective Systemic inflammatory responses in cancer patients are important factors for nutrition and prognosis. This study evaluates the association between tooth loss, occlusal status, and prognostic nutritional index (PNI). Methods A total of 93 patients with gastric cancer were included. These parameters were investigated the following: stage, body mass index (BMI), total lymphocyte count, C‐reactive protein (CRP), PNI, and albumin (ALB). Patients were divided into three groups by Eichner classification (group A had contact in four support zones; group B had in one to three zones or in anterior region; and group C had no contact). PNI assumed 40 or less undernutrition. Multiple regression analysis was performed (PNI, dependent variable; Eichner index, main independent variable), using four independent variables (sex, age, BMI, and CRP) as adjustment factors. Results The mean ± SD PNI in groups A, B, and C was 43.0 ± 4.7, 41.7 ± 5.2, and 36.7 ± 7.7, respectively. A significant positive correlation was found between the number of teeth, both ALB, and PNI. ALB and PNI differed significantly between groups A and C (ALB, p = .0003; PNI, p = .005). Conclusion We recommend a preoperative dental evaluation for assessing the nutritional status of patients with gastric cancer.

The film structures and gas sensing properties of tin oxide ultrafine particle films deposited under oxygen pressures between 0.05 and 5 Torr have been studied. The ultrafine particle film having porous columnar structure is found to have high sensitivities in detecting humidity or combustible gases when operated at elevated temperatures. The films can be made selectively sensitive to these gases by choosing the film depositing conditions and the operating temperature.Tin dioxide, SnO2, in its pure form is an n-type metal oxide semiconductor. Its electrical conduction results from the existence of point defects (oxygen vacancies and interstitial tin atoms) which act as donors (1). Some unique properties of SnOs make the material useful for many applications such as resistor, NESA glass, and so on. Recently, SnO2 has attracted special interest as a gas sensor material.The properties of SnO~ in the form of sintered polycrystals (2), thin films (3-5), or thick films (6) as gas sensors have been reported. Some of the gas sensors of above types have been put into practical applications for sensing combustible gases. However, the gas sensing mechanism, the change of electrical characteristics by means of gas adsorption, of these sensors has not been explained satisfactorily up to the present time.Models which have been proposed to explain the conductance modulation in the senors by gas adsorption are:1. Electron transfer between adsorbed gas molecules and SnO~ materials, i.e., change in surface conductance (7).2. Change of SnO~ composition, i.e., change in bulk conductance (8).3. Potential barrier height modulation at the grain boundary of polycrystalline samples (9). 4. Field effect transistor action at the neck parts of polycrystalline samples (10).In any model, special attention must be paid to the surface quality (proportion of surface to volume) of the gas sensor materials, because the adsorption process responsible for the change in conductance takes place at the boundary between the gaseous and solid states.We have developed a highly reproducible procedure for preparing the ultrafine particles of the metal oxide and .the films (11). The ultrafine particles are grown by the evaporation of the metal in a low oxygen pressure atmosphere where ultrafine particles of metal oxide are deposited and form films having, for example, porous columnar structure on silica glass or silicon substrafes covered with SiO~ thin film. The SnOe typical ultrafine particle film fabricated by using this technology has the porous columnar structure constructed from the ultrafine particles having the median particle size of several tens of angstroms (in sintered polycrystalline materials, the particle size is more than several thousands of angstroms) :The unique characteristics of these SnO~ ultrafine particle films are as follows.1. Each ultrafine particle has a large specific surface area because of the smallness of its particle size. Therefore, the portion of the surface energy in the total energy of the particle becomes large and the s...