David P. Serrano

Clinical applicability of the new EORTC/MSG classification for invasive pulmonary aspergillosis in patients with hematological malignancies and autopsy-confirmed invasive aspergillosis.

Diagnosis of invasive pulmonary aspergillosis (IPA) is often difficult. Recently, the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) has proposed new criteria for the classification of invasive fungal infections. We have studied the clinical applicability of this classification in 22 patients with hematological malignancies who had IPA at autopsy. While alive, according to the EORTC/MSG criteria, only 2 patients were classified as having proven IPA, 6 as probable, 13 as possible, and 1 was unclassifiable. Of the patients, 64% had no microbiological or major clinical criteria before death. Although the EORTC/MSG criteria are an important step forward in the standardization of definitions used for IPA in clinical research studies, most patients who die with extensive lung disease only reach a level of possible or probable IPA during life, further highlighting that these guidelines should not be used for clinical decision-making.

Comparable survival between HIV+ and HIV- non-Hodgkin and Hodgkin lymphoma patients undergoing autologous peripheral blood stem cell transplantation.

Autologous stem cell transplantation (ASCT) has been successfully used in HIV-related lymphoma (HIV-Ly) patients on highly active antiretroviral therapy. We report the first comparative analysis between HIV-Ly and a matched cohort of HIV(-) lymphoma patients. This retrospective European Group for Blood and Marrow Transplantation study included 53 patients (66% non-Hodgkin and 34% Hodgkin lymphoma) within each cohort. Both groups were comparable except for the higher proportion of males, mixed-cellularity Hodgkin lymphoma and patients receiving granulocyte colony-stimulating factor before engraftment and a smaller proportion receiving total body irradiation-based conditioning within the HIV-Ly cohort. Incidence of relapse, overall survival, and progression-free survival were similar in both cohorts. A higher nonrelapse mortality within the first year after ASCT was observed in the HIV-Ly group (8% vs 2%), predominantly because of early bacterial infections, although this was not statistically significant and did not influence survival. Thus, within the highly active antiretroviral therapy era, HIV patients should be considered for ASCT according to the same criteria adopted for HIV(-) lymphoma patients.

Analysis of factors associated with low peripheral blood progenitor cell collection in normal donors

BACKGROUND: Predictive factors of the response to rHuG–CSF in normal donors have not been extensively studied.

Catalytic conversion of polyolefins into fuels over zeolite beta

The catalytic degradation of polypropylene and both low- and high-density polyethylene over different samples of zeolite beta has been investigated. Zeolite beta synthesized by the fluoride method has a low activity for the cracking of polyolefins, which is related to its large crystal size (12 μm) and poor aluminium incorporation. In contrast, zeolite beta synthesized from amorphous xerogels consists of small crystallites (⩽200 nm) and allows all the polyolefins to be degraded with high conversion (40–60%) and good selectivity towards C5–C12 hydrocarbons (60–70%), heavier products being hardly obtained (<6%). The incorporation of titanium into the BEA structure has been proved to enhance the catalytic activity, as denoted by the highest conversion per Al atom obtained with the Ti–Al-beta sample compared to Al-beta.

Single-unit umbilical cord blood transplantation from unrelated donors in patients with hematological malignancy using busulfan, thiotepa, fludarabine and ATG as myeloablative conditioning regimen

Attempts to optimize outcomes in cord blood transplantation (CBT) by using new conditioning regimens and standardization of cord blood unit selection are warranted. In all, 88 patients (18 children and 70 adults) with hematological malignancy from nine Spanish institutions underwent a single-unit CBT after an i.v. BU-based myeloablative conditioning regimen. All evaluable patients except one engrafted. The overall cumulative incidence (CI) of myeloid engraftment was 94% at a median time of 19 days. In multivariate analysis, nonadvanced disease stage was the only factor with a favorable impact on myeloid engraftment. The CI of acute GVHD grades II–IV and chronic extensive GVHD were 24% each. The CI of nonrelapse mortality at 100 days, 180 days and 5 years was 14, 23 and 44%, respectively. The 5-year CI of relapse was 18%, whereas disease-free survival (DFS) was 46%, 39% and 11% for patients transplanted in early, intermediate and advanced stages of the disease, respectively. Our study shows high rates of engraftment with fast neutrophil recovery in patients undergoing single-unit CBT using a BU-based conditioning regimen. Long-term DFS can be achieved in a substantial number of patients with high-risk hematological malignancies, particularly when transplanted in an early stage of the disease.

Preparation of TS-1 by wetness impregnation of amorphous SiO2—TiO2 solids: influence of the synthesis variables

Abstract TS-1 has been synthesized by wetness impregnation of amorphous SiO 2 TiO 2 solids with TPAOH solutions and subsequent crystallization under autogenous pressure, the influence of the different variables involved being studied. The SiO 2 TiO 2 cogel used as raw material has been prepared following a two step (acid-base) sol-gel process which leads to the formation of Si O Ti bonds previously to the zeolite crystallization. The titanium content of TS-1 can be controlled through the variation of the raw SiO 2 TiO 2 composition, although a limit of the Ti/(Ti + Si) × 100 molar ratio around 2.3% in titanium effectively incorporated to the zeolite framework has been observed, even when starting from cogels with low Si/Ti ratios. The size and morphology of the crystals depend on the synthesis variables, small crystallites with 0.2 μm of diameter being obtained at high TPAOH concentration. The kinetics of TS-1 crystallization by this method is very fast in spite of taking place in static conditions. Thus, pure TS-1 can be achieved at 170°C in just 6 h of synthesis. All TS-1 samples were tested as catalysts for n-hexane oxyfunctionalization, high activities and selectivities being obtained with most of them.

Thermal and catalytic cracking of polyethylene under mild conditions

Abstract Thermal and catalytic cracking of both high and low-density polyethylene (HDPE and LDPE, respectively) under mild conditions have been investigated in order to study the properties of the solid waxy product so obtained. The catalysts employed were n-HZSM-5 and HY zeolites, amorphous silica–alumina, activated carbon, Pd charcoal powder and mesoporous aluminosilicate materials (MCM-41), with and without impregnated Pd. The best results achieved in the LDPE degradation with regard to stability and homogeneity of the waxy product were obtained using MCM-41 as catalyst. The high BET surface area, uniform mesoporosity and medium acid strength of this catalyst promotes the polymer cracking according to a random scission mechanism, as well as, the development of hydrogen transfer reactions which reduce the olefinic character of the solid product. On the other hand, the product obtained from HDPE has a higher homogeneity than that coming from LDPE, leading to a waxy product with better quality for potential applications.

Crystallization mechanism of all-silica zeolite beta in fluoride medium

Abstract The crystallization mechanism of pure silica zeolite beta in a fluoride medium has been investigated through the characterization of samples obtained at different synthesis times. The crystallization takes place in the presence of tetraethyl ammonium and fluoride ions at neutral pH, following a non-conventional mechanism based on the reorganization of an amorphous gel phase. The solid yield, referenced to the silica weight, remains almost constant and close to 100% during the whole crystallization process. Likewise, the amount of TEA + and F − ions present in the solid is not significantly changed as its crystallinity varies from 0% to 100%. The amorphous material initially observed is formed by a gel phase consisting of non-isolated primary units around 10–30 nm size distributed throughout the gel phase. The first crystals detected in the system are very large, with sizes around 7 μm. These crystals growth directly from the amorphous solid phase through a process of aggregation and densification of the primary units. The crystals finally observed in highly crystalline samples have sizes around 14 μm. This crystallization mechanism based on solid–solid transformations is probably favored by the low solubility of the silica species in the fluoride medium under neutral pH.

Conversion of low density polyethylene into petrochemical feedstocks using a continuous screw kiln reactor

Thermal and catalytic degradation of low-density polyethylene (LDPE) has been investigated using a screw kiln reactor provided with two zones of reaction temperature. Thermal degradation experiments carried out at different temperatures and screw speeds have shown that this continuous system is suitable for the LDPE degradation, product outputs up to c.a. 100 g/h being obtained. Compared to a conventional batch reactor, the screw kiln system leads to a lower formation of gaseous products, whereas overcracking of the heavy fractions is also reduced. These differences are probably originated by the intimate contact and the same residence times for all the product fractions that exist within the screw reactor, which is in contrast with the selective and fast withdrawal of volatile products taking place in the batch system. In the catalytic experiments, a mesoporous MCM-41 type aluminosilicate has been used as catalyst, being continuously fed to the screw reactor mixed with the raw plastic material. In these conditions, yields up to 80% towards hydrocarbons within the gasoline range (C5C12) have been obtained. Moreover, high amounts of C7 and C8 hydrocarbons are present in the gasoline fractions, which is assigned to catalytic oligomerization reactions that selectively affect to C3 and C4 gaseous hydrocarbons.

Donor age-related differences in PBPC mobilization with rHuG–CSF

BACKGROUND: Data on the administration of rHuG–CSF to normal donors <18 years old are very limited.