Detection of the Oxidation Area by Spectrophotometry: Regional and Temporal Changes in Anodic Oxidation on Titanium in Bipolar Electrochemistry

This study investigated the temporal change in the oxidation area on a titanium (Ti) bipolar electrode (BPE) subjected to bipolar anodization in a direct current (DC) electric field using a spectrophotometer. The rectangular Ti sheet used as a BPE was horizontally positioned at the center of a cell. After the DC bipolar anodization, the oxidized area was detected nondestructively and visually using a specific interference color that depends on the thickness of the barrier-type oxide film formed on the Ti BPE. The change in the L*a*b* color space corresponding to each interference color revealed that the oxidation area increased along the longitudinal axis of the BPE with the increasing electrolysis time by reflecting the change in the potential distributions on the BPE. As visually demonstrated, the area where the anodic reaction proceeded reached saturation at 90% of the BPE surface area.

Effects of size and position of an unconnected aluminum electrode on bipolar anodization in an AC electric field

The effects of the size and position of an aluminum bipolar electrode (BPE) on the uniformity of formation of anodic porous alumina in an alternating current electric field were investigated. Anodized specimens were dyed, and the resistance was measured after the specimens were anodized again. Phenomena observed during film formation indicated that the BPEs had unique potential distributions that strongly depended on their length and width. The color variations and electrical resistance of the BPEs were symmetrical and varied from the centers of the BPEs to their ends. When multiple BPEs were processed at the same time, their position in the non-uniform electric field was demonstrated to be an important factor for controlling the uniformity of film formation. The best results were obtained when the BPE was placed at the center of the defined space.

Facile synthesis of size- and shape-controlled freestanding Au nanohole arrays by sputter deposition using anodic porous alumina templates

To fabricate a freestanding through-hole Au membrane using an anodic porous alumina template, Au was deposited on the outermost surface of an anodic film followed by the removal of the template. Alumina templates with different dimensions (e.g. diameters and number of pores) were prepared by two-step anodization in the range of 40-80 V and pore-widening. The Au thin films were deposited onto alumina templates with well-controlled surface morphologies by sputter deposition using a commercially available ion sputter coater. After the removal of the alumina template, a variety of Au membranes with nanoholes, nanotubes, or branched pores were obtained, which reflect the morphology of the alumina template. When the sputtered Au penetrates the pores of the alumina film, Au nanotube arrays with an aspect ratio of ∼3 can be fabricated. The present method is much simpler than the traditional template process involving multi-step replication because there is no need to separate the alumina template from the aluminum substrate before Au deposition.

Bright Yellowish-Red Pigment Based on Hematite/Alumina Composites with a Unique Porous Disk-like Structure

Inspired by a bacteriogenic, iron-based oxide material and a traditional Japanese red pigment, a bright yellowish-red pigment was prepared by heating an Al-containing iron oxyhydroxide precursor. The obtained red pigment had a unique porous disk-like structure, comprising Al-substituted hematite particles and crystalline alumina nanoparticles. Although these disk-like structures loosely gathered to form an aggregate in powder, they can be easily dispersed into a single, disk-like structure by simple ultrasonic irradiation. The powder exhibited a bright yellowish-red color and high thermostability, making it attractive as a coloring material for various industrial products needing a bright-red color, high weather resistance, and durability. Quantitative color measurements revealed extremely high L*, a*, and b* values that are much greater than those of commercially available hematite. The thermostability test showed that even after exposure to high temperatures, the pigment retained the red color, indicating its high thermostability. The unique microstructure should be strongly related to the bright yellowish-red color and the high thermostability of the developed red pigment.

Effect of alcohol addition on the structure and corrosion resistance of plasma electrolytic oxidation films formed on AZ31B magnesium alloy

The effect of the addition of alcohol to a Na₃PO₄-based electrolyte on plasma electrolytic oxidation (PEO) of AZ31B magnesium alloy was investigated. Anodization with spark discharge was conducted in Na₃PO₄-based electrolyte containing various alcohols (e.g., ethanol, ethylene glycol, and glycerol) at a constant current density of 200 A m⁻² and a constant temperature of 25 °C. Voltage–time curves during the PEO process, the film structure, surface roughness, crystallographic structure, composition, corrosion resistance, and withstand voltage were investigated using various analytical equipment and electrochemical measurements. When the electrolyte containing alcohol was used, the initial bending voltage was higher than that observed using the basic electrolyte without alcohol addition, as was the oscillation voltage during the PEO process. For a given amount of electricity supplied, the addition of alcohol into the basic electrolyte tended to increase the thickness and corrosion resistance of PEO films formed while effectively reducing surface roughness. In particular, the addition of a polyhydric alcohol (i.e., ethylene glycol and glycerol) could act not only as a leveler for the formation of compact film but also as an enhancer for film qualities, such as corrosion resistance and withstand voltage. The patterns observed for Na₃PO₄-based electrolyte containing alcohol also hold for Na₂SiO₃-based electrolyte containing alcohol.

Alcohol used as an additive could act not only as a leveler for the formation of compact film but also as an enhancer for film qualities, such as corrosion resistance and withstand voltage.

Au-Capped GaAs Nanopillar Arrays Fabricated by Metal-Assisted Chemical Etching

GaAs nanopillar arrays were successfully fabricated by metal-assisted chemical etching using Au nanodot arrays. The nanodot arrays were formed on substrates by vacuum deposition through a porous alumina mask with an ordered array of openings. By using an etchant with a high acid concentration and low oxidant concentration at a relatively low temperature, the area surrounding the Au/GaAs interface could be etched selectively. Under the optimum conditions, Au-capped GaAs nanopillar arrays were formed with an ordered periodicity of 100 nm and pillar heights of 50 nm.

Well-Dispersed α-Fe2O3 Particles for Lead-Free Red Overglaze Enamels through Hydrothermal Treatment

The traditional Japanese overglaze ceramic, akae porcelain, typically known for Kakiemon-style wares, has been prized around the world for over 400 years. The red color of akae porcelain provides an attractive contrast to white porcelain. In recent years, because the use of leaded frit in making akae has been restricted by law owing to the effects of lead on human health and the environment, lead-free glass frit mixtures for overglaze ceramic wares have been developed in various porcelain production areas throughout Japan. However, current lead-free frit for red overglaze enamels produces a color that is duller than that of conventional leaded frit. Therefore, the development of red pigments that are suitable for use with lead-free frit is strongly desired. In this study, we used a hydrothermal process to prepare nanosized iron oxide and oxyhydroxide powders, which showed good particle dispersion in molten lead-free frit. The precursor paste was prepared by reacting iron nitrate with ammonium hydrogen carbonate and heated in a sealed vessel at 80-150 °C. The sample powder prepared at 90 °C was almost monophasic α-Fe₂O₃ (hematite) and exhibited the brightest red color (highest L*, a*, and b* values). This powder featured primary particles of ∼15 nm in diameter that aggregated to form secondary spherical particles of ∼100 nm in diameter. This powder was mixed with lead-free frit and applied as a red paint to a porcelain test piece. The resultant akae showed a bright red color with high L*, a*, and b* values that exceeded the values of akae prepared using conventional hematite powder. Microscopic analysis revealed that the hematite particles were well dispersed in the resultant glass layer, indicating that the hematite powders have good dispersibility in molten frit.

Indirect oxidation of aluminum under an AC electric field

Anodic porous alumina films can be formed by indirect oxidation under an alternating-current electric field without a direct electrical connection.

Sub-100-nm ordered silicon hole arrays by metal-assisted chemical etching

Sub-100-nm silicon nanohole arrays were fabricated by a combination of the site-selective electroless deposition of noble metals through anodic porous alumina and the subsequent metal-assisted chemical etching. Under optimum conditions, the formation of deep straight holes with an ordered periodicity (e.g., 100 nm interval, 40 nm diameter, and high aspect ratio of 50) was successfully achieved. By using the present method, the fabrication of silicon nanohole arrays with 60-nm periodicity was also achieved.

Triangle pore arrays fabricated on Si (111) substrate by sphere lithography combined with metal-assisted chemical etching and anisotropic chemical etching

The morphological change of silicon macropore arrays formed by metal-assisted chemical etching using shape-controlled Au thin film arrays was investigated during anisotropic chemical etching in tetramethylammonium hydroxide (TMAH) aqueous solution. After the deposition of Au as the etching catalyst on (111) silicon through a honeycomb mask prepared by sphere lithography, the specimens were etched in a mixed solution of HF and H2O2 at room temperature, resulting in the formation of ordered macropores in silicon along the [111] direction, which is not achievable by conventional chemical etching without a catalyst. In the anisotropic etching in TMAH, the macropores changed from being circular to being hexagonal and finally to being triangular, owing to the difference in etching rate between the crystal planes.

Hexagonal geometric patterns formed by radial pore growth of InP based on Voronoi tessellation

To fabricate ordered geometric patterns consisting of InP nanoporous structures, a photoresist mask with periodic opening arrays was prepared by sphere photolithography. The diameter and interval of the openings of the photoresist mask could be controlled independently by adjusting the diameter of silica spheres used as a lens and the exposure time. Through this resist mask with a two-dimensional (2D) hexagonal array of openings, the pore growth of InP during anodic etching was investigated. The isolated openings could act as initiation sites for the radial growth of pores, resulting in the formation of hexagonal geometric patterns based on Voronoi tessellation in 2D space. With further anodic etching, inside the substrate, the growth direction of the pores changed from radial to perpendicular relative to the substrate. Moreover, by removing domains consisting of nanopores by anisotropic chemical etching, the fabrication of InP microhole arrays with circular and triangular cross sections was also achieved.

Bioactivation of titanium surfaces using coatings of TiO(2) nanotubes rapidly pre-loaded with synthetic hydroxyapatite

Apatite depositions from simulated body fluid (SBF) have been widely used for the in vitro assessment of the bioactivity of bone- and dental-implant materials. In previous work, we reported that titanium-based implant materials can be coated with an anodic TiO(2) nanotube layer which can significantly stimulate apatite formation. In the present work, we demonstrate that the tubular nature of such coatings makes them highly suitable for the application of a treatment called "alternative immersion method (AIM)", which preloads the coatings with synthetic hydroxyapatite. This treatment is indeed found to additionally promote natural apatite formation significantly. To study the AIM effect, layers of nanotubes with various diameters and crystal structures (amorphous, anatase/rutile) were produced, AIM-treated, and the formation of apatite in SBF10 (10mmol1(-1) HCO(3)(-)) was evaluated. The results show a drastic enhancement of apatite deposition rates (in some cases >20-fold acceleration) for AIM-treated TiO(2) nanotube layers in comparison with non-treated TiO(2) surfaces.

Ordered hexagonal array of Au nanodots on Si substrate based on colloidal crystal templating

We report two types of site-selective metal deposition methods based on colloidal crystal templating. We discuss in particular the controllability of the morphology and crystallinity of Au nanodots depending of the choice of method.

Metal patterning on silicon surface by site-selective electroless deposition through colloidal crystal templating

Site-selective Cu deposition on a Si substrate was achieved by a combination of colloidal crystal templating, hydrophobic treatment, and electroless plating. Uniformly sized nano/microstructures were produced on the substrate using a monolayer coating of colloidal spheres instead of a conventional resist. The Cu patterns obtained were of two different types: networklike honeycomb and isolated-island patterns with a minimum period of 200 nm. Each ordered pattern with the desired intervals was composed of clusters of Cu nanoparticles with a size range of 50-100 nm. By the present method, it is possible to control the periodicity of metal arrays by changing the diameter of the colloidal spheres used as an initial mask and to adjust the shape of the metal patterns by changing the mask structure for electroless plating.

A phase I study of combination chemotherapy with gemcitabine and oral UFT for advanced non-small cell lung cancer

A phase I study was carried out to determine the optimal dose and administration schedule for combined UFT plus gemcitabine therapy in patients with non-small cell lung cancer. Twenty-four patients (including 11 patients previously treated with cisplatin as the key drug) received oral UFT 400 mg x m(-2) on days 1 to 14 with intravenous infusions of gemcitabine (800 mg x m(-2) on days 8 and 15, or 900 mg x m(-2) on days 8 and 15, or 900 mg x m(-2) on days 1, 8 and 15). The most appropriate dosing option appeared to be 400 mg x m(-2) per day of oral UFT for 14 consecutive days with 900 mg x m(-2) gemcitabine on days 8 and 15. Eight of the 24 patients achieved partial response. The combination chemotherapy UFT and gemcitabine was well tolerated and may benefit patients with advanced non-small cell lung cancer. A multicentre phase II study using a 3-weekly regimen is in progress.

Effect of tributyltin chloride on the release of calcium ion from intracellular calcium stores in rat hepatocytes

The effects of tri-n-butyltin chloride (TBT), an environmental pollutant, on the release of Ca(2+) from intracellular stores were investigated in isolated rat hepatocytes. Isolated hepatocytes permeabilized with digitonin were suspended in solution, and the concentration of extracellular Ca(2+) was measured, using a fluorescent Ca(2+) dye, fura-2. In the solution containing permeabilized hepatocytes that had been preincubated with 4.0 microM TBT for 30 min, the extracellular Ca(2+) concentration was high, but the inositol 1,4,5-trisphosphate (InsP(3))-induced increase in Ca(2+) concentration was suppressed, suggesting that the extracellular release of Ca(2+) in response to TBT treatment was from intracellular stores. Images of the Ca(2+) concentration in the intracellular stores of primary cultured hepatocytes loaded with fura-2 were obtained after digitonin-permeabilization, using digitalized fluorescence microscopy. The permeabilized hepatocytes that had been preincubated with 4.0 microM TBT for 30 min had a very low fura-2 fluorescence ratio (340/380 nm), suggesting that stored Ca(2+) was released. When the hepatocytes were treated with 4.0 microM TBT after digitonin-permeabilization, the decrease in the fura-2 fluorescence ratio was very small. However, when the permeabilized hepatocytes were incubated with 4.0 microM TBT and 2.0 microM NADPH, the decrease was enhanced, raising the possibility that TBT might be metabolized to the active form(s), thus releasing Ca(2+) from intracellular stores. When the hepatocytes were preincubated with 0.1 microM TBT for 30 min and then were permeabilized, the fura-2 fluorescence ratio was almost the same as that in the control permeabilized hepatocytes. However, the InsP(3)-induced decrease in the fluorescence ratio was suppressed significantly in the permeabilized hepatocytes. These results suggest that TBT released Ca(2+) from the intracellular stores at high concentrations, and suppressed the InsP(3)-induced Ca(2+) release at non-toxic low concentrations. It is probable that the latter effect was responsible for the previously reported suppression of Ca(2+) response induced by hormonal stimulations (Kawanish et al., Toxicol Appl Pharmacol 1999;155:54-61).

The influence of enhanced postoperative inflammation by the intrapleural administration of streptococcal preparation (OK-432) on the prognosis of completely resected non-small-cell lung cancer

BACKGROUND AND OBJECTIVES

It is not clear whether postoperative inflammation affects the prognosis of malignant disease.

METHODS

We retrospectively reviewed the patients with non-small-cell lung cancer who underwent a complete resection at the National Kyushu Cancer Center from 1989 to 1996. For the treatment of prolonged air leakage after a pulmonary lobectomy, 25 patients received an intrapleural injection of OK-432, a lyophilized preparation of the heat- and penicillin-treated Su-strain of the Streptococcus pyogenes group A3. All patients were males who were older than 50 years of age. As a control, we selected 164 male patients who were older than 50 years of age and not given OK-432 during the same period.

RESULTS

The administration of OK-432 in most patients was performed on the 4th day after the operation. Pleural drainage could be terminated in a mean of 5.5 days after the intrapleural administration of OK-432. In the control group, the serum C-reactive protein (CRP) level reached a peak on day 4 after the operation and returned to almost a normal level on day 14 after the operation. In the OK-432 group, the peak CRP level, which was significantly higher than that in the control group, was observed on day 7 after the operation and the elevated CRP level was maintained until 28 days after the operation. The mean level of CRP in the OK-432 group was significantly higher than that in the control on days 7, 14, and 28 after the operation. No significant difference was observed in the disease-free survivals between the two groups.

CONCLUSIONS

Based on the above findings, postoperative prolonged inflammation does not seem to affect the progression of subclinically residual tumor cells.

Direct influences of pro-inflammatory cytokines (IL-1beta, TNF-alpha, IL-6) on the proliferation and cell-surface antigen expression of cancer cells

Pro-inflammatory cytokines, e.g. interleukin 1 (IL-1), tumour necrosis factor alpha (TNF-alpha), IL-6 produced by surgical intervention or non-specific immunotherapy may directly affect both the growth and the metastasis of tumour cells. It is therefore important to clarify the direct influence of pro-inflammatory cytokines on tumour cells in order to obtain a better knowledge of anti-tumour therapy. Four human lung cancer cell lines were used. The tumour cells were incubated for 72 h in the presence of various concentrations of IL-1beta, TNF-alpha, or IL-6 and then the proliferative response was assessed by an MTT assay. After 14 days of culture with each pro-inflammatory cytokine, the cell-surface antigen expressions (HLA-class I, HLA-class II, CEA, sialyl Lewis(x)) were assessed by an immunocytochemical staining method. Among the various combinations of tumour cells (PC-9, PC-12, QG-56, QG-95) and cytokines (IL-1beta, TNF-alpha, IL-6), only TNF-alpha significantly exhibited an antiproliferative effect against PC-9 cells. However, various modulations of the cell-surface antigen expression by the cytokines were observed. The HLA-class I antigen expression of PC-9 was augmented by either TNF-alpha or IL-1beta. Furthermore, IL-1beta was able to induce CEA in PC-9, QG-56, and QG-95 cells while TNF-alpha was able to enhance the expression of sialyl Lewis(x)in QG-95 cells. Although the influence of pro-inflammatory cytokines on the growth of tumour cells was only slight, some modulations of the cell-surface antigen expression were notable. The augmentation of HLA-class I expression can thus improve the immunogenicity of tumour cells while the induction of CEA or sialyl Lewis(x)may therefore be associated with the promotion of metastasis.

UFT plus cisplatin with concurrent radiotherapy for locally advanced non-small-cell lung cancer

A phase II study of combined-modality treatment consisting of uracil and tegafur (in a molar ratio of 4:1 [UFT]) plus cisplatin (Platinol) and concurrent radiotherapy was conducted to evaluate the activity of this regimen in patients with locally advanced non-small-cell lung cancer. Eligible patients with cytologically or histologically confirmed, unresectable stage III non-small-cell lung cancer received UFT (400 mg/m2 orally on days 1 through 52) and cisplatin (80 mg/m2 intravenously on days 8, 29, and 50). Radiotherapy, with a total dose of 60.8 Gy, was delivered in 38 fractions on days 1 through 52. Among the 17 patients entered, 16 experienced partial responses (94%; 95% confidence interval, 83% to 100%). The median time to tumor progression was 30 weeks (range, 8 to 87 weeks), and the 1-year survival rate was 80%. Hematologic toxicity was moderate. Grade 3 leukopenia occurred in 10 patients (59%), but no grade 4 hematologic toxicity was observed. No grades 3 or 4 nonhematologic toxicities were reported. These observations suggest that oral UFT plus cisplatin with concurrent radiotherapy can be safely administered to patients with locally advanced non-small-cell lung cancer. The demonstrated antitumor activity is high, making this combined-modality treatment worthy of further investigation in a multi-institution trial.

Suppression of calcium oscillation by tri-n-butyltin chloride in cultured rat hepatocytes

The effects of tri-n-butyltin chloride (TBT), an environmental pollutant, on cytoplasmic free calcium ion concentration ([Ca2+]i) were investigated in primary cultured rat hepatocytes. A high concentration (4.0 microM) of TBT increased resting levels of [Ca2+]i and then induced cell blebs resulting in cell death within 2 h. The increase in [Ca2+]i, but not the cell death, depended on the presence of extracellular Ca2+, suggesting that the increase in [Ca2+]i is not critical for the cytotoxicity of TBT. A low concentration (0.1 microM) of TBT did not have any toxic effect (decrease in ATP content, decrease in viability, and shape change) on cultured hepatocytes and did not change [Ca2+]i. However, the calcium responses induced by phenylephrine, [Arg8]-vasopressin, and ATP were suppressed in the cells pretreated with 0.1 microM TBT for 30 min. The suppression was not observed in the cells pretreated with 0.1 microM TBT for only 1 min. Pretreatment with 0.1 microM TBT for 30 min had no effect on the inositol 1,4,5-triphosphate content or its increase in response to hormonal stimulation. These results suggest that TBT suppresses hormone-induced calcium responses at nontoxic low concentrations.

[Outpatient chemotherapy with oral UFT (tegafur and uracil) and cisplatin against metastatic non-small cell lung carcinoma--an effective case]

A 64-year-old man underwent a left pneumonectomy for squamous cell carcinoma of the left lung in July 1995. In May 1996, right pelvic bone metastasis occurred and was well controlled by the concurrent chemoradiotherapy; UFT (600 mg/body, day 1-14) and cisplatin (80 mg/m2, day 8) with a total 50.4 Gy of irradiation. In August 1996, left renal metastasis occurred, but regressed after two cycles of combination chemotherapy with UFT and cisplatin. In January 1997, multiple lung metastasis occurred. In accordance with the patient's request, combination chemotherapy was performed at the outpatient clinic. UFT (250 mg/m2) was given orally every day while cisplatin (60-80 mg/m2), fractionated in 3 or 5 days, was intravenously administered at an interval of 4 weeks or longer. The patient has continued the treatment for one year without serious (G3, 4) adverse events. During the treatment, the tumor growth was slow with a repeated cycle of progression and regression. The outpatient chemotherapy using UFT and cisplatin is considered to be useful, especially for the better quality of life of patients.

Long-term survivors with pN2 non-small cell lung cancer after a complete resection with a systematic mediastinal node dissection

OBJECTIVE

A substantial number of surgical patients with pN2 disease have survived longer than 5 years without any evidence of recurrence, although the surgical indications for those patients remain controversial. The present study was performed in order to clarify the clinical characteristics of the long-term survivors with pN2 disease.

METHODS

We retrospectively reviewed the cases of 111 patients with pN2 disease who had undergone a complete resection with a systematic mediastinal lymph node dissection from 1974 through 1991.

RESULTS

Of the 111 patients with pN2 disease, 20 survived longer than 5 years after a surgical resection. When both the pre- and post-operative conditions were compared between the long-term survivors and the others, the long-term survivors were characterized by significantly higher proportions of cN0 disease (P = 0.031), pT1 disease (P = 0.004), skip metastasis without hilar node metastasis (P = 0.028), and metastasis of a single mediastinal station (0.044). Of those characteristics, only the likelihood of having cN0 disease could be pre-operatively determined. The survival rate of such a population with cN0-pN2 disease was 34.5% at 5 years and 29.6% at 10 years after a complete resection, respectively.

CONCLUSIONS

Pathologic N2 patients with some favorable prognostic factors can survive long-term after a complete resection combined with a systematic mediastinal lymph node dissection. At present, due to the lack of any effective adjuvant therapy, a systematic mediastinal node dissection should be routinely performed even in patients with cN0 disease.

HLA class I and class II expression of pulmonary adenocarcinoma cells and the influence of interferon gamma

BACKGROUND

The clinico-biological significance of HLA (both class I antigen and class II one) expressed on tumor cells still remains controversial.

METHODS

Tumor cells were freshly separated from 33 surgical specimens of pulmonary adenocarcinoma. The tumor cells were incubated for 24 h in the presence or absence of IFN-gamma (130 International Units/ml). After incubation, the cells were cytocentrifuged onto glass slides and immunostained with either an anti-HLA class I (A, B, C) monoclonal antibody or anti-HLA class II (DR) one.

RESULTS

In 22 of 33 cases (66.7%), the HLA class I were individually expressed by more than 60% of tumor cells while so were the HLA class II in 15 (45.4%). No significant correlation was observed between the HLA class I expression and the HLA class II one. The proportion of HLA class I-positive tumor cells correlated with neither the grade of histological differentiation nor the stage of disease. In contrast, the proportion of HLA class II-positive tumor cells correlated with both the grade of histological differentiation and the stage. In most cases, IFN-gamma was found to increase the proportion of class II-positive tumor cells as well as that of class I-positive cells.

CONCLUSIONS

The above findings thus suggested that the HLA class II expression might therefore represent a manifestation of cellular differentiation and that IFN-gamma may, as a result, have the potential to differentiate cancer cells.

Cancer cells isolated from malignant pleural and peritoneal effusions inhibit phospholipase A2 activity in human polymorphonuclear leukocytes

We studied the influence of cancer cells on the LTB4 production by human polymorphonuclear leukocytes (PMN). The cancer cells were isolated from malignant pleural effusion specimens taken from two patients or from a peritoneal effusion specimen of one patient. While human PMN produced LTB4 following stimulation with A23187, the addition of cancer cells inhibited LTB4, 5-HETE and 12-HETE production by PMN in a cell number-dependent manner, while the cancer cell lines also showed a similar inhibition. The addition of lysate of the breast cancer cells also inhibited in a dose-dependent manner the production of LTB4 by PMN following stimulation with A23187. The addition of arachidonic acid completely reversed the inhibition of PMN-LTB4 production by the addition of the breast cancer cell lysates, thus suggesting inhibition at the phospholipase A2 level. The addition of this lysate to the partially purified human cytosolic PLA2 also inhibited the PLA2 activity. In contrast, the addition of lymphoma cells isolated from metastatic lymphnodes did not inhibit the LTB4 production from PMN. Since LTB4 is one of the important chemotactic factors for PMN and monocytes, these findings suggest that the inhibition of the PLA2 activity by the cancer cells thus results in a reduced production of LTB4 from PMN and contributes to a predisposition to develop severe infection in patients with advanced cancer.

Diagnosis of visceral pleural invasion in resected lung cancer using a jet stream of saline solution

BACKGROUND

Visceral pleural invasion by the tumor is an important prognostic factor in patients undergoing resection for lung cancer. We developed a method to detect more accurately the presence of visceral pleural invasion in resected lung cancer.

METHODS

The surface of the visceral pleura over 90 resected peripheral tumors was irrigated twice with a jet stream of saline solution using a 20-mL syringe with a 21-gauge needle, and then the fluid, which contained desquamated cells, was collected for cytologic analysis. When cancer cells were found in the collected fluid, the tumor was judged to have invaded the visceral pleura.

RESULTS

Thirty-eight (42%) resected tumors were identified as having visceral pleural invasion either by our new method or by pathologic examination. Twenty-four cases were detected by the jet stream of saline method alone, 5 by pathologic examination alone, and 9 by both techniques. The sensitivity and accuracy of the two approaches in the diagnosis of visceral pleural invasion were 87% and 94%, respectively, for our new method, and 37% and 73%, respectively, for pathologic examination (p < 0.0001). Furthermore, among 38 patients who had a tumor demonstrating visceral pleural invasion, 5 (13%) and 9 (24%) patients, respectively, had cancer cells in the pleural effusion and intrapleural lavage fluid.

CONCLUSIONS

Our findings suggest that our method is useful in detecting cancer invasion of the visceral pleura, which is considered one of the causes of malignant effusion.

Intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis

BACKGROUND AND OBJECTIVES

We recently developed a new intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis found at thoracotomy in non-small cell lung cancer patients. In the present study, the efficacy and adverse events of this treatment as well as the pharmacokinetics of cisplatin in the blood after the treatment were evaluated.

PATIENTS AND METHODS

Twenty-one patients received the treatment for 15 minutes after completing the intrathoracic surgical procedures. The total and free platinum levels in the blood of five patients were then measured. As a control, 29 patients without such treatment were reviewed retrospectively.

RESULTS

The survival rates in the treatment and non-treatment groups were similar. The pleural disease free survival of the treated patients was, however, significantly higher than that of the non-treated patients. Such pleural disease as effusion and the growth of the pleural disseminated tumors only appeared in three of the 21 (14%) treated patients while 26 of 29 (90%) non-treated patients had clinically detected pleural disease. The blood platinum levels after the treatment were extremely low and such low levels probably induced no systemic adverse events after the treatment. The only adverse event of this treatment was an increase in the postoperative drainage volume.

CONCLUSIONS

These observations seem to suggest that intraoperative intrapleural hypotonic cisplatin treatment for carcinomatous pleuritis found at thoracotomy can, at least, delay the appearance of the pleural disease without any adverse events.

Failure in resection of multiple pulmonary metastases from colorectal cancer

BACKGROUND

To clarify whether or not multiple pulmonary metastases from colorectal cancer are contraindicated for a surgical resection, we retrospectively evaluated the influence of the number of pulmonary metastases on both the postthoracotomy survival and the pattern of the first failure.

METHODS

From 1981 to 1993, 36 patients underwent a complete resection for pulmonary metastases from colorectal cancer.

RESULTS

Of the various factors investigated including gender, primary site, disease-free interval, tumor size, the number of metastases, type of resection, and the history of hepatic metastases, only the number of pulmonary metastases was found to be significantly related to postthoracotomy survival. The rate of disease-free survival at 5 years was 62% for solitary metastasis (n = 17), 35% for two metastases (n = 8), and 0% for four or more metastases (n = 11). The pattern of failure also differed according to the number of pulmonary metastases. In particular, the incidence of local recurrence at the primary site increased with the number of pulmonary metastases (ie, 1 of 17 patients with a solitary metastasis, 3 of 8 with two metastases, and 6 of 11 with four or more metastases).

CONCLUSIONS

These results suggest that multiple metastases might indicate the presence of local recurrence at the primary site; therefore, in cases of multiple pulmonary metastases, the primary site should be thoroughly explored.