Analysis of linear and cyclic oligomers in polyamide-6 without sample preparation by liquid chromatography using the sandwich injection method. II. Methods of detection and quantification and overall long-term performance.

By separating the first six linear and cyclic oligomers of polyamide-6 on a reversed-phase high-performance liquid chromatographic system after sandwich injection, quantitative determination of these oligomers becomes feasible. Low-wavelength UV detection of the different oligomers and selective post-column reaction detection of the linear oligomers with o-phthalic dicarboxaldehyde (OPA) and 3-mercaptopropionic acid (3-MPA) are discussed. A general methodology for quantification of oligomers in polymers was developed. It is demonstrated that the empirically determined group-equivalent absorption coefficients and quench factors are a convenient way of quantifying linear and cyclic oligomers of nylon-6. The overall long-term performance of the method was studied by monitoring a reference sample and the calibration factors of the linear and cyclic oligomers.

Analysis of linear and cyclic oligomers in polyamide-6 without sample preparation by liquid chromatography using the sandwich injection method. I. Injection procedure and column stability.

We report a method for reliable routine polymer sample introduction with minimal bias, a separation method of the first six linear and cyclic oligomers by liquid chromatography, quantification using group equivalents and long term method performance. Injecting a polymer sample in a mobile phase containing an aqueous non-solvent often results in blocked systems as the polymer precipitates in the connecting capillaries. In this first part we focus on a new injection technique, in which the dissolved polyamide is placed between two zones of formic acid, preventing the polymer to precipitate before it reaches the column. Development of this sandwich injection method makes direct injection of the polymer into an aqueous acetonitrile gradient feasible. The oligomeric polyamide recovery of this technique, extraction, dissolution/precipitation and direct injection on a hexafluoro-isopropanol (HFIP) gradient were compared. With the sandwich injection method the polymer remains on the column, slowly changing the stationary phase. The influence of this on resolution and retention was studied. Column stability allows sixty injections before cleaning or replacing the column is necessary.

Dose-response relationship of epirubicin-based first-line chemotherapy for advanced breast cancer: a prospective randomized trial.

PURPOSE: We compared prospectively the antitumor efficacy of two combination chemotherapy regimens with two different dose levels of epirubicin as first-line treatment for advanced breast cancer. PATIENTS AND METHODS: One hundred forty-one fully assessable patients were randomized to receive either our intensified schedule (group A, n = 71) of epirubicin 50 mg/m2 on days 1 and 8 (every 3 weeks), or a non-intensified program (group B, n = 70) in which epirubicin was only administered on day 1. Both groups also received fluorouracil (5 FU) and cyclophosphamide 500 mg/m2 on day 1 of each course. RESULTS: A statistically significant difference in response rate was observed (69% in group A v 41% in group B, P < .001) for both locally advanced (LA) and recurrent metastatic (RM) disease. Response duration (22 v 14 months, P < .01) and time to progression (TTP; 19 v 8 months, P < .02) were also significantly improved. Overall survival was similar in both groups. However, univariate and/or multivariate analyses showed a meaningful relationship between type of treatment allocated, dose-intensity (DI) of epirubicin, and response rate, as well as between TTP and survival. Ultimately, TTP and survival were also influenced by further treatment modalities, namely, hormonotherapy and chemotherapy. CONCLUSION: This study validates prospectively the concept of a dose-response relationship for an anthracycline-based chemotherapy in previously untreated advanced breast cancer.

[Pulmonary hyalinizing granuloma. Apropos of 2 new cases]. / Les granulomes hyalinisants pulmonaires. A propos de 2 nouveaux cas.

Pulmonary hyalinising granuloma are nodular or localised fibrosing lesions of the pulmonary parenchyma and are single or multiple. We report two new cases of this disorder which is rare, as only 62 cases have been published in the literature. It is a pathology with few symptoms, sometimes revealed by general signs. Radiologically there are nodules which are most often round or oval, intra-parenchymal, well demarcated, single or multiple. The histological appearance is characteristic: the centre of the granuloma consists of a network of dense collagen fibres which are lamellar separated by clear spaces; the periphery is the seat of rich cellular infiltration of plasmocytes and lymphocytes in the peri-vascular region. Most often there is a spontaneous benign outcome. The frequent association of pulmonary hyalinising granuloma in fibrotic disorders and the similarity in the histological appearance leads to the hypothesis of a common pathogenesis in these disorders.

Cytosine arabinoside for induction, salvage, and consolidation therapy of adult acute lymphoblastic leukemia.

During A-ALL induction treatment, HD-ara-C (2.5 g/m2 IV, day 1), does not produce any beneficial effect, whereas the hematologic toxicity is increased. A 3-month consolidation phase comprising intermittent MTX, ara-C and 6-TG is not significantly affecting either DFI or survival in A-ALL. The association of HD-ara-C and m-AMSA appears to be a promising salvage therapy for the 20% A-ALL refractory to first induction therapy. The quality of autologous bone marrow graft, harvested after HD-ara-C, seems to be impaired as suggested by a delayed recovery of PMN and platelets. HD-ara-C (3 g/m2 X N) given the days before cyclophosphamide and TBI as conditioning treatment for BMT does not seem to induce prohibitory additional toxicity. Whether HD-ara-C was given four to six times or eight to 12 times gave no significant difference in early toxicity.

Effects of transfusion on serum iron, serum lactate dehydrogenase and platelets in megaloblastic anemia.

In 11 patients with megaloblastic anemia, transfusion of packed erythrocytes or washed erythrocytes invariably resulted in a decline in plasma iron concentration to a range of 20-90 microgram/dl (3.6-16 mumol/l) after 36 to 48 hours. The same phenomenon was observed in two of six cases of ineffective erythropoiesis without megaloblastosis and in none of five cases of aplastic anemia. The observed changes did not result from a specific hematinic response or from iron uptake by a non-erythroid compartment. In megaloblastic anemia, alteration in marrow function in response to transfusion was reflected by plasma iron kinetics and serum lactate dehydrogenase values, which indicated marked reductions in both marrow hyperplasia and ineffective erythropoiesis. Transfusion in megalobastic anemia was also responsible for a 50% reduction in platelet count after 2 to 6 days. The significance of these changes is discussed.