[Host immunity in colorectal cancer patients treated with TS-1 plus CPT-11]

TS-1/CPT-11 treatment for the patients with advanced colorectal cancer is expected to be equal to FOLFOX and FOLFIRI regimen. The aim of this study was to investigate the relationship between host immunity and this regimen. Four patients were enrolled in this study. Host immunity was investigated before and after chemotherapy. PHA response, serum IAP level and the productions of any cytokines did not change significantly before and after the chemotherapy. Although these changes were not significant: both Th1/Th2 ratio and NK cells ratio were decreased, and the ratio of suppressor T cells was increased. These results suggest that TS-1/CPT-11 regimen may influence host immunity a little bit worse.

Short Term Outcomes of High Power (80 W) Potassium-titanyl-phosphate Laser Vaporization of the Prostate

PURPOSE

We have evaluated the safety and efficacy of 80 W potassium-titanyl-phosphate (KTP) laser in the treatment of patients with lower urinary system symptoms (LUTS) due to benign prostatic hyperplasia.

MATERIALS AND METHODS

A total of 186 patients with LUTS have been evaluated using the International Prostate Symptom Score (IPSS) and quality of life (QoL) scoring questionnaire. Volume of prostate, post-micturition volume of residual urine (PVR), maximum flow rate (Qmax) and serum prostate specific antigen (PSA) values were determined. Laser vaporization of the prostate with an 80 W KTP was applied to all the patients. IPSS and QoL scores were evaluated on postoperative days 30, 90 and 180. The below values were measured on the postoperative days mentioned respectively: Qmax-15, 30 and 90; PSA-1, 15, 30 and 60; PVR-90.

RESULTS

The results of 186 patients, who underwent KTP laser treatment, have been evaluated. Mean age of the patients was 66+/-8 (47-90). Mean volume of prostates, mean operative time and mean energy delivery were 48.1+/-13.2 ml (26-70), 57+/-17 minutes (10-120) and 105+/-37 kJ (20-350), respectively. Following the procedures, Foley catheters were removed after a mean time of 7.59+/-0.9 hours (6-13). Compared with the preoperative period, IPSS, QoL, PVR and Qmax values decreased significantly during the postoperative period (p<0.01). Mean preoperative PSA value was 2.59+/-0.9 ng/ml (0.28-4). There were statistically significant increases in PSA values on postoperative day 1 (p<0.001). However, on postoperative day 15, PSA values decreased as low as preoperative values. There was moderate dysuria in 55 (30%) patients with a mean duration of 2 months and mild hematuria in 10 (18%) patients with a mean duration of 1 month postoperatively. Urinary tract infection occurred in 12 (6%) patients. None of the patients had fever or required re-catheterization. We observed contracture of the bladder neck in 2 (1%) patients and clot retention in 2 (1%) patients. Urinary incontinence due to operation was not observed.

CONCLUSIONS

KTP laser vaporization of the prostate is a treatment method which can be used in patients at high risk of anesthesia. This procedure is safe and effective in that it quickly relieves bladder outlet obstruction symptoms and has a low rate of postoperative complications. However, long-term follow-up studies are called for in order to ascertain whether the results of this procedure are durable or not.

The in vitro absorption of microfine zinc oxide and titanium dioxide through porcine skin

Microfine metallic oxides such as titanium dioxide or zinc oxide have been found to be highly protective against harmful UV rays. Because their long-term use could potentially lead to health effects if significant amounts of these microfine metallic oxides would be absorbed through the skin, the in vitro absorption of microfine zinc oxide and titanium oxide in cosmetic formulations through porcine skin was investigated. In the experiments with a microfine zinc oxide formulation, the mean total recoveries of Zn were in the range from 102% to 107% of the total Zn applied. Virtually the total amount of applied Zn was recovered in the first five tape strips. The amounts of Zn found in the skin membrane and the receptor fluid were comparable in untreated, vehicle treated or test substance treated skin preparations. The absorption-time plots from diffusion cells treated with the vehicle did not differ from those treated with the ZnO containing formulation. In the experiments with microfine titanium dioxide formulations T-Lite SF-S and T-Lite SF, mean total recoveries of Ti ranged from 98% to 100% and 86% to 93% of the total Ti applied, respectively. Virtually the total amount of applied Ti could be removed from the skin surface by washing. The amounts of titanium found in the tape strips and skin preparations were in the order of the analytical determination limit. No Ti was found in the receptor fluid at any sampling time. The results show that neither zinc or titanium ions nor microfine zinc oxide or titanium dioxide particles were able to penetrate porcine stratum corneum. Therefore, from the absence of internal exposure we conclude that their use in sunscreens does not pose a health risk.

Comparative Pulmonary Toxicity Inhalation and Instillation Studies with Different TiO2 Particle Formulations: Impact of Surface Treatments on Particle Toxicity

Most pigment-grade titanium dioxide (TiO(2)) samples that have been tested in pulmonary toxicity tests have been of a generic variety-i.e., generally either uncoated particles or TiO(2) particles containing slightly hydrophilic surface treatments/coatings (i.e., base TiO(2)). The objectives of these studies were to assess in rats, the pulmonary toxicity of inhaled or intratracheally instilled TiO(2) particle formulations with various surface treatments, ranging from 0-6% alumina (Al(2)O(3)) or alumina and 0-11% amorphous silica (SiO(2)). The pulmonary effects induced by TiO(2) particles with different surface treatments were compared to reference base TiO(2) particles and controls. In the first study, groups of rats were exposed to high exposure (dose) concentrations of TiO(2) particle formulations for 4 weeks at aerosol concentrations ranging from 1130-1300 mg/m(3) and lung tissues were evaluated by histopathology immediately after exposure, as well as at 2 weeks and 3, 6, and 12 months postexposure. In the second study, groups of rats were intratracheally instilled with nearly identical TiO(2) particle formulations (when compared to the inhalation study) at doses of 2 and 10 mg/kg. Subsequently, the lungs of saline-instilled and TiO(2)-exposed rats were assessed using both bronchoalveolar (BAL) biomarkers and by histopathology/cell proliferation assessment of lung tissues at 24 h, 1 week, 1 and 3 months postexposure. The results from these studies demonstrated that for both inhalation and instillation, only the TiO(2) particle formulations with the largest components of both alumina and amorphous silica surface treatments produced mildly adverse pulmonary effects when compared to the base reference control particles. In summary, two major conclusions can be drawn from these studies: (1) surface treatments can influence the toxicity of TiO(2) particles in the lung; and (2) the intratracheal instillation-derived, pulmonary bioassay studies represent an effective preliminary screening tool for inhalation studies with the identical particle-types used in this study.

[A case of multiple bone metastasis from gastric carcinoma given chemotherapy with TS-1 combined with cisplatin]

We experienced a case of bone metastatic recurrence from gastric carcinoma that responded to TS-1 combined with low-dose cisplatin (CDDP) therapy. A 63-year-old male patient presented with multiple bone metastases 5 years after radical surgery for advanced gastric carcinoma. The titer of serum CEA showed extremely high levels of 18,000 ng/ml. The uptake area was found at all vertebrae, ribs, and pelvis by scintigraphy 99mTc-HMDP. The chemotherapy regimen, performed in the outpatient clinic, comprised daily oral administration of 80 mg/m2 of TS-1 for 14 days and CDDP 20 mg/m2 infusion (day 1). This regimen was repeated every 3 weeks for 9 months. After that, severe pain diminished and the titer of serum showed CEA had improved to 599 ng/ml. The uptake at the multiple bone metastasis was found to have decreased by scintigraphy. The patient was able to resume his full social activities. TS-1/low-dose CDDP therapy seems to be applicable for the treatment of gastric carcinoma with bone metastasis.

Novel nanoparticulate carrier system based on carnauba wax and decyl oleate for the dispersion of inorganic sunscreens in aqueous media

The purpose of this study was to characterize carrier systems for inorganic sunscreens based on a matrix composed of carnauba wax and decyl oleate. Ultraviolet radiation attenuators like barium sulfate, strontium carbonate and titanium dioxide were tested. The lipid matrices were used either as capsules or as accompanying vehicles for the pigments in aqueous dispersions. Manufacturing was performed using high pressure homogenization at 300bar and a temperature of 75 degrees C. To evaluate the effect of the pigments on the crystalline structure of the wax-oil mixture, X-ray diffraction and differential scanning calorimetry were used. Further parameters determined were particle size, polydispersity index, z-potential, viscosity and sun protection factor (SPF). Transmission electron microscopy was also applied for visualization of nanoparticles. The X-ray diffraction patterns and the melting points of the lipid mixtures remained unchanged after the pigments were added. The particle sizes of the encapsulated species ranged from 239 to 749.9nm showing polydispersity values between 0.100 and 0.425. Surface charge measurements comprising values up to -40.8mV denoted the presence of stable dispersions. The formulations could be described as ideal viscous presenting viscosities in a range of 1.40-20.5mPas. Significant increases in SPF up to about 50 were reported after the encapsulation of titanium dioxide. Freeze fracture micrographs confirmed the presence of encapsulated inorganic crystals.

Growth factor-loaded scaffolds for bone engineering

The objective of the study presented here was to investigate the bone inductive properties as well as release kinetics of rhTGF-beta1- and rhBMP-2-loaded Ti-fiber mesh and CaP cement scaffolds. Therefore, Ti-fiber mesh and porous CaP cement scaffolds were provided with these growth factors and inserted in subcutaneous and cranial implant locations in rats and rabbits. In vitro, a rapid release of rhTGF-beta1 was observed during the first 2 h of the Ti-fiber mesh scaffolds. During this time, more than 50% of the total dose of rhTGF-beta1 was released. Following this initial peak, a decline in the level of rhTGF-beta1 occurred. After 1 week, the entire theoretical initial dose was observed to have been released. This in contrast to the rhTGF-beta1 and rhBMP-2 release of the porous CaP cement scaffolds. Here, no substantial initial burst release was observed. The scaffolds showed an initial release of about 1% after 1 day, followed by an additional marginal release after 1 week. Histological analysis revealed excellent osteoconductive properties of non-loaded Ca-P material. Inside non-loaded Ti-mesh fiber scaffolds, also bone ingrowth occurred. Quantification of the bone ingrowth showed that bone formation was increased significantly in all scaffold materials by administration of rhTGF-beta1 and rhBMP-2. Consequently, we conclude that the release kinetics of growth factors from porous CaP cement differs from other scaffold materials, like metals and polymers. Nevertheless, orthotopic bone formation in a rabbit cranial defect model was stimulated in rhTGF-beta1- and rhBMP-2-loaded CaP cement and Ti-fiber mesh scaffolds compared with non-loaded implants.

Effects of titanium particle size on osteoblast functions in vitro and in vivo

The formation of titanium (Ti)-wear particles during the lifetime of an implant is believed to be a major component of loosening due to debris-induced changes in bone cell function. Radiographic evidence indicates a loss of fixation at the implant-bone interface, and we believe that the accumulation of Ti particles may act on the bone-remodeling process and impact both long- and short-term implant-fixation strengths. To determine the effects of various sizes of the Ti particles on osteoblast function in vivo, we measured the loss of integration strength around Ti-pin implants inserted into a rat tibia in conjunction with Ti particles from one of four size-groups. Implant integration is mediated primarily by osteoblast adhesion/focal contact pattern, viability, proliferation and differentiation, and osteoclast recruitment at the implant site in vivo. This study demonstrates the significant attenuation of osteoblast function concurrent with increased expression of receptor activator of nuclear factor kappaB ligand (RANKL), a dominant signal for osteoclast recruitment, which is regulated differentially, depending on the size of the Ti particle. Zymography studies have also demonstrated increased activities of matrix metalloproteinases (MMP) 2 and 9 in cells exposed to larger Ti particles. In summary, all particles have adverse effects on osteoblast function, resulting in decreased bone formation and integration, but different mechanisms are elicited by particles of different sizes.

Dietary sources of inorganic microparticles and their intake in healthy subjects and patients with Crohn's disease

Dietary microparticles are non-biological, bacterial-sized particles. Endogenous sources are derived from intestinal Ca and phosphate secretion. Exogenous sources are mainly titanium dioxide (TiO2) and mixed silicates (Psil); they are resistant to degradation and accumulate in human Peyer's patch macrophages and there is some evidence that they exacerbate inflammation in Crohn's disease (CD). However, whether their intake differs between those with and without CD has not been studied. We aimed to identify dietary microparticle sources and intakes in subjects with and without CD. Patients with inactive CD and matched general practice-based controls (ninety-one per group) completed 7 d food diaries. Intake data for dietary fibre and sucrose were compared as positive controls. All foods, pharmaceuticals and toothpastes were examined for microparticle content, and intakes of Ca and exogenous microparticles were compared between the two groups. Dietary intakes were significantly different between cases and controls for dietary fibre (12 (SD 5) v. 14 (SD 5) g/d; P=0.001) and sucrose (52 (SD 27) v. 45 (SD 18) g/d; P=0.04) but not for Ca. Estimated median TiO2 and Psil intakes (2.5 and 35 mg/individual per d respectively, totalling 10(12)-10(13) microparticles/individual per d) were broadly similar to per capita estimates and while there was wide variation in intakes between individuals there was no significant difference between subjects with CD and controls. Hence, if exposure to microparticles is associated with the inflammation of CD, then the present study rules out excess intake as the problem. Nonetheless, microparticle-containing foods have now been identified which allows a low-microparticle diet to be further assessed in CD.

Efficacy of Sunscreens Containing Pre-Tocopheryl in a Surviving Human Skin Model Submitted to UVA and B Radiation

The aim of the present study was to evaluate by means of histological and biochemical tools the additive efficacy of pre-tocopheryl during photoprotection using a sunscreen containing mineral sunblock agents 50B-10A (TiO(2), ZnO) and pre-tocopheryl in comparison to a cream containing only mineral sunblock agents 50B-10A. For this purpose, an ex vivo technique and an acetone-impaired human skin model were used in order to approximate in vivo metabolic conditions. Creams were topically applied to the surface of the epidermis and submitted to UV radiations. Then, human skin explants were maintained alive in organ culture for 3 days. Free radical modulation was analysed by hydroperoxide assay. Epidermal (involucrin, cell proliferation, stratum corneum lipids) and dermal changes (elastic fibres and collagen) were studied. Analysis of ex vivo surviving skin samples impaired by UV irradiations and treated with the mineral sunscreen 50B-10A showed a significant decrease in hydroperoxide production and an improvement in the elastic fibre and collagen network in the dermis. Adding pre-tocopheryl to this formula induced an increase in involucrin and epidermal lipids such as squalenes and ceramides. Altogether, these results confirm the efficacy of the combination of a mineral sunscreen and pre-tocopheryl in photoprotection and free radical protection.

Effect of silver-carrying photocatalyst "Hikari-Gintech" on mycobacterial growth in vitro

The antimycobacterial activity of "Hikari-Gintech" powder, which has photocatalytic activity, was examined in vitro. Both powder dissolved in liquid and Hikari-Gintech-coated cloths showed strong antimycobacterial activity against Mycobacterium tuberculosis H37Rv, M. bovis BCG Pasteur, multi-drug-resistant M. tuberculosis (a clinical isolate) and M. avium. Hikari-Gintech powder appeared to affect mycobacterial cell wall metabolism rather than mycobacterial DNA because no damage to mycobacterial DNA was detected after spraying with Hikari-Gintech solution.

The Effect of Lung Burden on Biopersistence and Pulmonary Effects in Rats Exposed to Potassium Octatitanate Whiskers by Inhalation

The effect of lung burden on biopersistence and histopathological changes caused by potassium octatitanate whiskers (POW) which is one of the asbestos substitutes were investigated for 1-yr and 4-wk inhalation periods. In the 1-yr inhalation experiment, male Wistar rats were exposed to POW (TW) for 6 h/d, 5 d/wk under the same conditions as a previous study of POW (PT1, JFM fiber) which is made by different manufacturer. The exposure concentration was 1.9 +/- 0.7 mg/m(3) and the mass median aerodynamic diameter (MMAD) and geometric standard deviation (GSD) in the chamber were 1.6 microm and 2.9. Rats were sacrificed at 3 d and 1 yr after the inhalation experiment and TW deposits in the lungs were determined by ICP-AES. Lung burden at 3 d and 1 yr after the inhalation was 2.39 +/- 0.50 mg and 1.37 +/- 0.96 mg, respectively, the deposition fraction was 8.1% and biological half time (BHT) was 15 months. Aggregated dust cells and mild fibrotic changes around these dust cells were observed in the exposed rat lung. These results were almost the same as those obtained in the previous 1-yr PT1 study. In the 4-wk inhalation experiment, to investigate the effect of lung burden on biopersistence and histopathological change, male Wistar rats were exposed to PT1. The exposure concentration was 102 +/- 21 mg/m(3), MMAD (GSD), the geometiric mean length and diameter (GSD) of the PT1 in the chamber were 1.6 microm (3.0), 2.2 microm (1.8) and 0.33 microm (1.5), respectively. Rats were sacrificed at 3 d, 1 wk, and 1, 3, 6 and 12 months after the inhalation experiment. The lung burden of POW at 3 d after 4 wk inhalation was 1.49 +/- 0.19 mg, which was close to the estimated amount of overload. The BHT of the total mass (4.1 months) was not prolonged, but aggregated dust cells were observed in the subpleural region and around the bronchioles and mild fibrotic changes were observed only around the dust cells at one year after the 4-wk inhalation. It is considered that the excessive exposure which impairs the function of alveolar macrophage mediated clearance may cause the aggregation of dust cells and fibrotic changes.

Interstitial gene delivery in human xenograft prostate tumors using titanium metal seeds

Gene therapy is a promising approach for the treatment of cancers. Strategies for gene vector delivery include systemic and local-regional approaches. Intratumoral delivery of vectors has generally employed direct injections into single or multiple locations throughout the tumor volume. However, this approach leads to nonuniform distributions of reagents within tumors and becomes cumbersome as the required number of injections is increased. We have investigated the effectiveness of an interstitial plasmid gene delivery based on using tiny metallic seeds (GeneSeeds) analogous to technology used for brachytherapy. Feasibility for interstitial use of GeneSeeds was demonstrated expressing reporter plasmids (green fluorescence protein or beta-galactosidase) in human xenograft prostate tumors. Immunohistochemical analysis confirmed effective interstitial delivery, vector expression, and distributions of reporter genes within tumors. Applicability of GeneSeeds for delivery of radiosensitizing cytokines was examined by generating a cytokine [tumor necrosis factor-alpha (TNF-alpha)] expressing vector under the cytomegaloviral promoter and interstitially implanting GeneSeeds with this vector into prostate cancer tumors. TNF-alpha protein expression was observed around the ends of seeds and decreasing in an exponential gradient as a function of distance. The expression of TNF-alpha resulted in tumor growth delay of a human prostate cancer xenograft. These results demonstrate the feasibility of applying interstitial delivery of gene expressing vectors for the treatment of human cancers.

[Alterations in expression of F-actin and DNA of fluid shear stress treated-mesenchymal stem cells affected by titanium particles loading]

Particulate wear debris within the bone-prosthesis microenvironment generated by normal wear and corrosion of orthopaedic implants is considered to be one of the main factors responsible for chronic aseptic inflammation and development of osteolysis in the long-term instability and failure of total joint arthroplasty. While the decrease in bone volume caused by wear debris-induced osteolysis could have been compensated by enough new bone matrix secreted by osteoblasts. Actually, the normal osteoblastic population depend on the regular differentiation and proliferation of their progenitor cells--bone marrow mesenchymal stem cells (MSCs). This study aims to investigate the potential mechanism for the rat MSCs cytotoxicity upon exposure to Titanium (Ti) particles. Rat mesenchymal stem cells (rMSCs) isolated from 3-month-old male Sprague-Dawley rats by Percoll intensity gradient method were cultured in DMEM medium (low glucose) supplemented with 10% fetal bovine serum, 100 U/ml penicillin, and 100 micrograms/ml streptomycin in a humidified incubator with 5% CO2 at 37 degrees C. In order to gain the homogenous cell population, rMSCs were passaged to 3-4th subpassage which were used in all the experiment groups. Then rMSCs were seeded in the 6 well culture plates and exposed to three different circle diameters (mean size, TD1: 0.9 micron, TD2: 2.7 microns, TD3: 6.9 microns) with three different concentrations (0.1 wt%, 0.05 wt%, 0.01 wt%, W/V) at different durations (8 h, 16 h, 24 h,), respectively. Unexposed rMSCs were used as control. In the given periods of Ti loading, fluid shear stress (FSS) was applied to each group cells. The expression of F-actin and DNA of the rMSCs at the indicated time were determined with laser confocal scanning microscopy and image analysis software. The results showed that there was up-regulation expression of F-actin in the rMSCs without Ti particles loading but in the presence of FSS. Ti particles loading can suppress the expression of F-action and DNA of rMSCs, but this down-regulation response varied with the three circle diameter, concentrations and durations of Ti particles. Among three kinds of diametrically different Ti particles, submicron Ti particles (0.9 micron) had the greatest suppressive response on rMSCs, together with some apoptosis bodies. Under the same diameter condition, the inhibition induced by Ti particles loading was in a manner dependent on the particles concentration and exposure duration. The reductive effects produced from 0.1 wt% Ti was the greatest and earliest among the responses from Ti particles at three different concentrations; and the lower the concentration, the weaker the repressive influence. Furthermore, with the elongation of exposure to Ti particles, the expression of F-actin and DNA decreased gradually, the lowest level was at 32 h. These findings demonstrated that Ti particles loading can attenuate rMSCs' viability in a manner dependent on the circle diameter, particles concentration, treatment period, suggesting that a reduction in the number of viable MSCs together with a compromise of the their differentiation into functional osteoblast may exacerbate aseptic loosening of total joint implant. Further investigation into particles-mediated suppression of MCSs viability may reveal novel mechanism of implant loosening and aid in development and application of osteolytic drug therapy and the optimization of design and selection of future orthopaedic biomaterials, thereby improving long-term compatibility and stability for arthroplasty patients.

[Complete response of primary tumor in a case of advanced gastric cancer with liver metastasis treated by TS-1 plus divided administration of CDDP]

A 62-year-old female patient was hospitalized for general fatigue and appetite loss. Type 3 gastric cancer (moderate differentiated adenocarcinoma) with liver metastasis (S8) and direct invasion to the retro-peritoneal space and duodenal third portion was detected by endoscopic and radiographic examination. This case was judged to be unresectable from these findings. TS-1 plus divided administration of CDDP was performed. TS-1 (100 mg/day) was administrated from day 1 to 21 followed by 14 days rest as one course. CDDP (20 mg/m2) was infused for 2 hours on day 1, 8, and 15. One course was done in the hospital, and the following 2 courses as ambulatory treatment. Grade 2 neutropenia was observed as an adverse reaction. At the completion of 3 courses, partial response in the primary tumor, complete response in the duodenal third portion and no change in the liver metastasis were assessed by examination. Because of this remarkable down-staging, distal gastrectomy and radiofrequency ablation (RFA) for liver metastasis were performed. There was no evidence of direct invasion to the other organs from the primary tumor in intraoperative findings. Pathological examination revealed the disappearance of carcinoma cell in the resected stomach and the surrounding lymphnodes. In conclusion, this chemotherapy regimen has an excellent antitumor effect with low toxicities. Therefore, this regimen was comparatively safe for outpatients and was an effective neo-adjuvant chemotherapy.

A new porous titanium-nickel alloy: part 2. Sensitization, irritation and acute systemic toxicity evaluation

Porous titanium-nickel (PTN) represents a new biomaterial with orthopedic applications as a long-term implant. Because of its nickel content, PTN was tested for its potential to stimulate sensitization, irritation, and systemic toxicity reactions after semi-physiological extraction. In order to do so, an in vivo biocompatibility evaluation was performed following three ISO-standardized methods using accepted animal models for immunity testing: the classical skin sensitization assay (Buehler patch test) in guinea pigs, the rabbit intracutaneous test, and the systemic injection test in mice. The Buehler patch test in guinea pigs revealed no significant change in skin reactions such as erythema or swelling between the induction and the challenge period. In the rabbit intracutaneous irritation test, no irritation or sensitization reactions were observed in saline-extracted PTN samples. Negligible to slight irritation was observed at some of the sites involving PTN samples extracted in cottonseed oil, however the resulting primary irritation index was similar to the one elicited by the blank solution itself. Finally, no toxic symptoms were observed with any of the mice injected with porous titanium-nickel extracts during the acute systemic toxicity test. Based on the above results, porous titanium-nickel is considered to be a non-sensitizing, non-irritant, and non-toxic biomaterial for medical applications.

[Usefulness of TS-1 and lentinan combination immunochemotherapy in advanced or recurrent gastric cancer--pilot study aiming at a randomized trial]

The quality of life (QOL) of patients with advanced or recurrent gastric cancer is poor and their immunocompetence is low, making it important to conduct chemotherapy while at the same time improving their QOL and maintaining their immunocompetence. To improve QOL and increase compliance by reducing the side effects but not the antitumor effect of TS-1, a 2-week regime with 2-week administration of TS-1, and a 1-week drug-free interval in combination with the immunotherapeutic agent lentinan (LNT) was started in 5 patients with advanced or recurrent gastric cancer. Toxicity, efficacy, QOL, and immunological parameters were investigated preliminarily to examine whether or not usefulness of lentinan could be evaluated. QOL scores for appetite, nausea/vomiting, and abdominal pain/diarrhea showed improvement, although not in statistically significant values. The Th2 (CD4-positive, IL4-positive T cells) response in peripheral blood decreased significantly. TS-1 and lentinan combination immunotherapy was carried out safely with advanced recurrent gastric cancer. In order to examine the usefulness of LNT combined use, it was thought that a randomised trial using toxicity with not only efficacy but QOL and immunological parameters as indicators would be beneficial.

[A case of gastric cancer responding to TS-1, with long survival of 16 months]

We report the case of a 47-year-old woman with Stage VI gastric cancer accompanied by p2 grade dissemination which responded to chemotherapy using TS-1. Treatment of the patient with daily oral administration of 80 mg TS-1 for 2 cycles resulted in partial regression in the size of the primary lesion. Side effects were only seen after administration of 1 month, as mild pigmentation easily controlled by white vaseline ointment. After 6 cycles of administration, the effect on the gastric mucosal lesion decreased, and the wall thickness and stenosis of the antrum were increased. The patient has been administered 10 cycles of chemotherapy with no myelosupression, and maintains a good quality of life.

[A patient with peritoneal metastasis from gastric cancer who responded to weekly chemotherapy with paclitaxel on the third line and could take meal]

We report a patient with peritoneal metastasis from gastric cancer who responded to weekly chemotherapy with paclitaxel (TXL) as the third line treatment and could take meals for half a year. The patient was a 64-year-old man who underwent total gastrectomy for advanced gastric cancer with peritoneal metastasis. He was first treated with TS-1 as an outpatient treatment; however, tumor markers rose. He could not take meals and had to be hospitalized. CPT-11 was infused on the second line, but due to disease progress, the patient was administered weekly TXL. TXL (70 mg/m2) was infused over 1 hour after short premedication. Administration was continued for 3 weeks followed by 1 week rest. The tumor markers decreased, and he could take meals and was discharged from hospital. The toxic events were leukopenia (grade 2), alopecia (grade 2) and pneumonia (grade 3).

Examination of cytotoxicity and mutagenicity of AH26 and AH Plus sealers

AIM

To study in vitro the cytotoxic and mutagenic effects of AH26 and AH Plus.

METHODOLOGY

Cytotoxic effects on Chinese hamster V79 cells were determined by counting viable cells following incubation with eluations of AH26 and AH Plus. In one set of experiments, the materials were mixed, set for 1 h and then eluted with dimethyl sulphoxide (DMSO) for 1 h, 24 h and 7 days. In the other set, AH26 and AH Plus were mixed and set for 1 h, 24 h and 7 days in physiological saline then crushed and eluted in DMSO for 24 h. The cytotoxic effects of these eluates were evaluated. Three concentrations were chosen to examine the mutagenic effects of AH26 and AH Plus: 5.57, 16.7 and 55.7 microg mL(-1). The structural chromosomal aberration analysis and micronucleus test were performed on human lymphocytes according to standard procedures.

RESULTS

Dose-response curves of cell survival were obtained. Both materials were shown to be cytotoxic in doses larger than 55.7 microg mL(-1), except for AH26, after 7 days setting time. AH Plus was also shown to be toxic in concentrations of 16.7 microg mL(-1), except after 7 days setting time. Neither AH26 nor AH Plus induced a significant increase of chromosomal aberrations or micronuclei induction at any setting time or concentration.

CONCLUSION

There was no mutagenicity found for AH26 and AH Plus on human lymphocytes in highly controlled conditions in vitro.

Distribution of sunscreens on skin

The effectiveness of sunscreens was originally achieved by incorporation of soluble organic UV absorbers such as cinnamates and others into cosmetic formulations. Determinations of the sun protection factor (SPF) of emulsions containing different organic UV absorbers clearly indicate that the efficacy depends on the absorption characteristics of each single UV filter substance. Nowadays, micronised pigments such as titanium dioxide or zinc oxide have also been found to be protective against harmful UV rays. Our investigations using optical and electron microscopy proved that neither surface characteristics, particle size nor shape of the micronised pigments result in any dermal absorption of this substance. Micronised titanium dioxide is solely deposited on the outermost surface of the stratum corneum and cannot be detected in deeper stratum corneum layers, the human epidermis and dermis.

[Pathomechanisms of impaired wound healing by metallic corrosion products]

BACKGROUND

Metallic materials of variable chemical composition have been used in dental practice for a long time. Complications with respect to tissue healing after insertion of implants are well documented. In this paper we present relevant aspects of the related fields of inflammation and repair processes and focus on the pathomechanisms of this impaired healing response.

MODULATION OF WOUND HEALING

This latter process is modulated by specific metal ions released by corrosion activity as well as by wear particles, which influence the function of the participating cell types (e.g. endothelial cells).

IN VITRO MODELS

In this context, in vitro models are presented that permit study of isolated aspects of the complex sequence of events at the biomaterial-tissue interface. Furthermore, newly developed, computer-assisted methods allowing an objective quantification of biomaterial/corrosion product-induced effects on complex processes, such as angiogenesis in vitro, are demonstrated. Because of the central importance of titanium implants in maxillofacial surgery, new experimental approaches to study possible negative effects are presented. Finally, the relevance of such studies for clinical implantology is evaluated.

Decomposition of gas-phase trichloroethene by the UV/TiO2 process in the presence of ozone

The decomposition of gas-phase trichloroethene (TCE) in air streams by direct photolysis, the UV/TiO2 and UV/O3 processes was studied. The experiments were carried out under various UV light intensities and wavelengths, ozone dosages, and initial concentrations of TCE to investigate and compare the removal efficiency of the pollutant. For UV/TiO2 process, the individual contribution to the decomposition of TCE by direct photolysis and hydroxyl radicals destruction was differentiated to discuss the quantum efficiency with 254 and 365 nm UV lamps. The removal of gaseous TCE was found to reduce by UV/TiO2 process in the presence of ozone possibly because of the ozone molecules could scavenge hydroxyl radicals produced from the excitation of TiO2 by UV radiation to inhibit the decomposition of TCE. A photoreactor design equation for the decomposition of gaseous TCE by the UV/TiO2 process in air streams was developed by combining the continuity equation of the pollutant and the surface catalysis reaction rate expression. By the proposed design scheme, the temporal distribution of TCE at various operation conditions by the UV/TiO2 process can be well modeled.

Photocatalytic oxidation of heptane in the gas-phase over TiO2

In this paper, gas-phase photocatalytic oxidation (PCO) of heptane over UV-illuminated TiO2 was carried out at ambient temperature in a batch reactor. Complete oxidation of heptane with almost stoichiometric production of CO2 and H2O was observed. The intermediates detected were propanal, butanal, 3-heptanone, 4-heptanone and carbon monoxide. A scheme of the possible mechanism for PCO of heptane over TiO2 was suggested. Langmuir-Hinshelwood kinetics equation was obtained from the results at different initial concentrations of heptane, oxygen, moisture and light intensity. The photocatalytic activity of TiO2 can be sustained indefinitely. This can be attributed to the production of water in the system, which can replenish the consumed hydroxyl radicals.