Potentiation of Paclitaxel Cytotoxicity by Inostamycin in Human Small Cell Lung Carcinoma, Ms-1 Cells

In the present study, we found that inostamycin increased the ability of paclitaxel to induce apoptosis in Ms-1 cells. A considerably higher concentration of paclitaxel was required for the induction of apoptosis in Ms-1 cells than in other cell lines tested. Treatment of Ms-1 cells with inostamycin, an inhibitor of phosphatidylinositol (PI) synthesis, reduced the dosage of paclitaxel required to induce cell death by apoptosis. This effect of inostamycin is specific to Ms-1 cells, and inostamycin did not increase the cytotoxicity of other antitumor drugs such as adriamycin, vinblastine, methotrexate, cisplatin, etoposide, or camptothecin in Ms-1 cells. Addition of inostamycin to paclitaxel-treated cells caused a significant increase in the sub G1 peak, representing apoptosis, which was accompanied by a decrease in the G2/M peak seen in paclitaxel-treated Ms-1 cells, without affecting paclitaxel-inhibited tubulin depolymerization. Moreover, paclitaxel did not enhance inostamycin-inhibited PI synthesis. The expression levels of Bcl-2, Bax, and Bcl-X_L were not changed following the co-treatment with inostamycin plus paclitaxel, whereas the activated form of caspase-3 was markedly increased. Thus, inostamycin is a chemosensitizer of paclitaxel in small cell lung carcinoma Ms-1 cells.     

Effect of Anti-TNF Therapy and Vitamin D Derivatives on the Proliferation of Peripheral Blood Mononuclear Cells in Crohn's Disease

Infliximab treatment demonstrated clinical and endoscopic benefits in active refractory and fistulizing Crohn's disease. The aim of this research was to investigate the proliferative response of peripheral blood mononuclear cells (PBMC) obtained from patients with active and fistulizing Crohn's disease treated with infliximab therapy. PBMC proliferation and VDR protein levels were also studied when 1,25(OH)2D3 or its analogues (EB 1089, KH 1060) were added to cells cultures. At day 5 of culture, the proliferation of PBMC obtained from patients responsive to the therapy showed a remarkable decrease (about 60%) at T6 (after two infusions) with respect to T0 (before the first infusion). On the contrary, in the unresponsive patient, the proliferative response was four times higher at T6 in comparison with T0. Vitamin D derivatives induced a decrease in cell proliferation higher in responsive patients than in the unresponsive one. Increased VDR levels during therapy were registered only in the unresponsive patient. Our results indicate that PBMC proliferation and VDR expression may be useful indicators to predict the response of patients with Crohn's disease to the infliximab therapy.     

Phase II study of 2-week TS-1 administration followed by 1-week rest for gastric cancer

BACKGROUND/AIMS: TS-1 monotherapy with 4-week administration followed by 2-week rest is used as the community standard treatment for metastatic gastric cancer in Japan. However, according to a postmarketing survey, the percentage of patients who received three or more courses was only 44.6%; for the reasons of discontinuation due to exacerbation of symptoms or adverse reactions during the first or second course. Therefore, we conducted the phase II study of 2-weeks administration with TS-1 followed by a 1-week rest against metastatic gastric cancer, aiming for mitigation of adverse reactions without reduction of antitumor effect. METHODOLOGY: Thirty-five patients were enrolled between 2001 and 2003 at nine institutes in Japan. One cycle of TS-1 treatment whose dosage was 80 mg/m2/day consisted of administration for 2 weeks followed by a 1-week rest. The primary endpoint was overall response rate and the secondary endpoints were safety and feasibility. RESULTS: There were 6 PRs, 13 NCs, 11 PDs, and 5 patients were not evaluable (NE), yielding a response rate of 17%. The median survival time of all patients was 290 days. Severe adverse Grade 3 or 4 reactions were observed in 8 (23%) patients. The rate of patients who received six or more courses was 43%. The cumulative rate of the relative total administration days was 93%. CONCLUSIONS: We concluded that the schedule of TS-1 administration for 2 weeks followed by a 1-week rest might not be superior to the conventional schedule (4 weeks on and 2 weeks off) with regard to the antitumor effect, adverse reactions and prolonged medication, although it was acceptable from the point of view of survival.     

Cuffed anastomosis for above-knee femoropopliteal bypass with a stretch expanded polytetrafluoroethylene graft

PURPOSE: To evaluate the patency and limb-salvage rates associated with cuffed anastomosis in above-knee femoropopliteal (FP) bypasses using prosthetic grafts. METHODS: Between January 1997 and December 2005, 96 patients (99 limbs) underwent above-knee FP bypass grafting for peripheral vascular disease, with disabling claudication in 81%. All grafts were 6-mm, thin-walled, ringed, expanded polytetrafluoroethylene (ePTFE) stretch grafts anastomosed to the above-knee segment of the popliteal artery in an end-to-side fashion, with a protruding area created around the anastomotic toe and an angle of less than 30 degrees between the graft and the artery. Postoperatively, graft patency was monitored by several objective methods. Patency and limb-salvage rates were calculated by actuarial methods and Kaplan-Meier analysis. RESULTS: The mean follow-up period was 40.4 months; 15 patients were lost to follow-up. The 1-, 3-, and 5-year primary graft patency rates were 94.5%, 88.2%, and 85.7%, respectively. The 1-, 3-, and 5-year secondary patency rates were 95.6%, 94.1%, and 90.8%. The 1-, 3-, and 5-year limb-salvage rates were 98.9%, 97.3%, and 97.3%. There were three graft infections. CONCLUSION: The use of a cuffed anastomosis in FP bypass with an ePTFE stretch prosthesis appears to increase graft patency rates.     

The CT-arthrography in the antero-inferior glenoid labral lesion: Pictorial presentation and diagnostic value

Objective:

To present the Computed Tomography (CT)-Arthrography appearance of the most common types of anterior labral lesion and to assess the diagnostic value of this technique in the detection and classification of the antero-inferior labral tears in glenohumeral joint instability.

Materials and Methods:

The pre-operative CT-Arthrography records of 43 patients, who underwent surgery for anterior shoulder instability, were retrospectively evaluated independently by two radiologists. The data were compared with arthroscopic results and the diagnostic accuracy of CT-Arthrography was calculated to detect the labral lesion and the agreement between the CT-Arthrography lesions classification and the arthroscopy classification.

Results:

The CT-Arthrography sensitivity, specificity and accuracy were: 92% / 89% (reader 1/reader 2), 86% / 86% and 91% / 88% respectively. The CT-Arthrography classification was correct in 86% of cases.

Conclusions:

CT-Arthrography appears to be an accurate means for identification and classification of the anterior labral tears and, identifying the labral degeneration, this technique can be very helpful in the selection of patient for arthroscopic stabilization of the shoulder.     

Involvement of disulfide bond formation in the activation of heparanase

Heparanase is overexpressed in many solid tumor cells and is capable of specifically cleaving heparan sulfate, and this activity is associated with the metastatic potential of tumor cells; however, the activation mechanism of heparanase has remained unknown. In this study, we investigated the link between disulfide bond formation and the activation of heparanase in human tumor cells. Mass spectrometry analysis of heparanase purified from a conditioned medium of human fibrosarcoma cells revealed two disulfide bonds, Cys127-Cys179 and Cys437-Cys542, and one S-cysteinylation at the Cys211 residue. It was shown that, although the formation of the Cys127-Cys179 bond and S-cysteinylation at Cys211 have little effect on heparanase function, the disulfide bond between Cys437 and Cys542 is necessary for the secretion and activation of heparanase. Thus, the present findings will provide a basis for the further refinement of heparanase structural studies and for the development of novel heparanase inhibitors.     

Lipoperoxidase activity of Pityrosporum: characterisation of by-products and possible rôle in pityriasis versicolor

Abstract Modification of pigmentation and damage of melanocytes are characteristic features of skin colonisation by Pityrosporum orbiculare hyphae in pityriasis versicolor (PV). The yeast is lipophylic and lipid-dependent, capable of oxidising unsaturated lipid components of skin surface, i.e. unsaturated fatty acids, cholesterol and squalene (SQ). The oxidation of unsaturated fatty acids gives rise to dicarboxylic acids (DA) which behave, in vitro, as competitive inhibitors of tyrosinase. In this work, we further investigate the oxidase activity of Pityrosporum in vitro, by evaluating (a) the generation of lipoperoxides in cultures supplemented with fatty acids at various degrees of unsaturation; (b) the mechanism of SQ oxidation; (c) the chemical characteristics of some by-products of lipoperoxidation; (d) the formation of peroxisomes in fungal cells. In cultures supplemented with the saturated palmitic acid (C16:0) and monounsaturated oleic acid (C18:1 n-9), low amounts of lipoperoxides were detected by a spectrophotometric test, whereas in cultures supplemented with di-unsaturated linoleic acid (C 18:2 n-6), significant concentrations were found. Gas chromatographymass spectrometry analyses showed the generation of linoleic acid hydroperoxides both in Pityrosporum cultures and following incubation of acetone powder of the fungus with the unsaturated fatty acid, indicating the presence of a lipoxygenase activity in the fungus. In cultures supplemented with linoleic acid plus SQ, and increase of lipoperoxide generation was observed and trans-trans farnesal and squalene epoxides have been identified. Electron microscopic examinations have evidenced peroxisomes in cells grown in the presence of linoleic acid, whereas they were not delected in cultures supplemented with oleic acid and palmitic acid. The metabolic activities of peroxisomes, through the formation of hydrogen peroxide and the subsequent generation of hydroxyl radicals, may account for the peroxidation of SQ, which is not a substrate of lipoxygenase. Following these results, we propose a mechanism for DA generation by Pityrosporum metabolism and hypothesize that the lipoperoxidation process induced by lipoxygenase activity of the fungus may be the key to understanding the clinical appearance of skin manifestation of PV.     

Impact of In Vivo Ranges of the Variances in the Flow Velocity Waveforms and Flow Split Ratio on the Hemodynamic Effects of the Anastomotic Cuff at Distal End-to-Side Anastomosis

Purpose The blood flow inside distal end-to-side anastomoses may be affected by inlet flow velocity profiles and outlet blood distribution ratios. This study investigated the in vivo range of these variables and their impact on the hemodynamic effects of an anastomotic cuff using a computational fluid dynamics approach. Materials and Methods Predesigned expanded polytetrafluoroethylene cuffed grafts were used in 22 femoropopliteal bypasses and straight grafts were used for 10 cases. The flow distribution was examined by angiographic techniques and the inlet flow velocity was determined by a spectral Doppler method. Results The caudal outflow distribution ratio was 95.6% ± 7.2% (75%–100%). The positive peak flow velocity was 1.66 ± 0.25 m/s. The ratio of the absolute value of the negative to positive peak velocity was 0.32 ± 0.12. The cuff increased wall shear stress along the artery floor regardless of the flow velocity profiles at 100% of the caudal distribution ratio but not at 75%. Conclusion The hemodynamics inside the anastomosis were thus found to be affected by these flow variables. The proper indications for the cuff should therefore not be decided based simply on the location of the anastomosis without taking the fluid dynamic factors in the vicinity of the anastomosis into full consideration.