New sesquiterpenes fromMaytenus species (Celastraceae). Taxonomic and chemotaxonomic considerations concerning chileanMaytenus

Three new dihydro--agarofuran sesquiterpenes from two species ofMaytenus were isolated and their structures were elucidated by means of¹H and¹³C NMR studies. The differences and similarities noted in the chemical content of the dihydro--agarofuran sesquiterpenes from the fourMaytenus species from Chile are in line with the taxonomic characterization of these species; their geographical distribution is also given.     

Hepatic metallothionein level and mixed function oxidase activity in fingerling rainbow trout (Oncorhynchus mykiss) after acute exposure to pulp and paper mill effluents

Hepatic metallothionein (MT) levels and mixed function oxidase (MFO) activity (7-ethoxyresorufin-o-deethylase or EROD) were measured in fingerling rainbow trout (Oncorhynchus mykiss) exposed to sublethal concentrations of 12 pulp and paper effluents, after completion of 96 h static acute lethality assays. Barring one primary-treated effluent where MFO levels were significantly depressed and two secondary-treated effluents where no significant MFO induction were observed, all other effluents triggered significant induction of MT and EROD, regardless of mill process/treatment or of effluent lethality and chemical characteristics. MT and EROD inductions were significant, however, at higher concentrations for secondary-treated effluents than for primary-treated ones. Lethal (96 h LC₅₀s) to sublethal (MT and EROD lowest observable effect concentrations) ratios were variable and indicated that significant biochemical effects were present at effluent concentrations that were roughly 4–33 (MT) and 3–59 (EROD) times lower than the LC₃₀. Enzyme induction ranged from 1.3 to 2.5-fold for MT and from 1.3 to 9.4-fold for EROD compared to controls. Limited chemical data available suggest that there were indeed classes of compounds present capable of inducing MT or EROD. Observed patterns of MT/MFO responses also suggest that contaminant interactions may have interfered with induction for some of the effluents studied. Refinements of this combined (sub)lethal bioassay procedure are envisaged to determine whether it can provide an efficient means of detecting hazardous chemicals in industrial wastewaters.     

Optical Properties of Self‐Assembled Cellulose Nanocrystals Films Suspended at Planar–Symmetrical Interfaces

Hierarchically structured materials comprising rod‐like, chiral, nanoparticles are commonly encountered in nature as they can form assemblies with exceptional optical and mechanical characteristics. These include cellulose nanocrystals (CNCs), which have a large potential for the fabrication of bioinspired materials mimicking those advanced properties. Fine‐tuning the optomechanical properties of assemblies obtained from CNCs hinges on the transformations from suspensions of liquid crystals to long‐range order in the dry state. So far, associated transitions have been studied using trivial interfaces such as planar substrates. Such transitions are explored as they evolve onto meshed supports. The meshed substrate offers a complex topology, as is encountered in nature, for the formation of CNCs films. The CNCs self‐assembly occurs under confinement and support of the framework bounding the mesh openings. This leads to coexisting suspended and supported nanoparticle layers exhibiting nematic and/or chiral nematic order. Optical microscopy combined with crossed polarizers indicate that the formation of the suspended films occurs via intermediate gelation or kinetic arrest of CNCs across the mesh's open areas. The formation of self‐standing, ultrathin films of CNCs with tunable optical properties, such as selective reflections in the visible range (structural color), is demonstrated by using the presented simple and scalable approach.     

Multi-scale modelling of silicon nanocrystal synthesis by Low Pressure Chemical Vapor Deposition

A multi-scale model has been developed in order to represent the nucleation and growth phenomena taking place during silicon nanocrystal (NC) synthesis on SiO₂ substrates by Low Pressure Chemical Vapor Deposition from pure silane SiH₄. Intrinsic sticking coefficients and H₂ desorption kinetic parameters were established by ab initio modelling for the first three stages of silicon chemisorption on SiO₂ sites, i.e. silanol Si―OH bonds and siloxane Si―O―Si bridges. This ab initio study has revealed that silane cannot directly chemisorb on SiO₂ sites, the first silicon chemisorption proceeds from homogeneously born unsaturated species like silylene SiH₂. These kinetic data were implemented into the Computational Fluid Dynamics Fluent code at the industrial reactor scale, by activating its system of surface site control in transient conditions. NC area densities and radii deduced from Fluent calculations were validated by comparison with experimental data. Information about the deposition mechanisms was then obtained. In particular, hydrogen desorption has been identified as the main limiting step of NC nucleation and growth, and the NC growth rate highly increases with run duration due to the autocatalytic nature of deposition.     

Horizontal Viscous Dam—Break Flow: Experiments and Theory

This paper considers dam-break flow occurring in a horizontal smooth channel. Experiments were carried out with highly viscous Newtonian fluids, e.g., glucose syrup–water solutions. The frontal shape of dam-break flow and its evolution, as well as the free-surface profile, were measured using video-photographic and ultrasonic equipment, respectively. New features of viscous dam-break flow are pointed out. Notably indicated are flow regimes and the effect of reservoir length as well as the effect of fluid viscosity on flow development. Equations describing dam-break flow are derived in nondimensional form, then compared with the results from experiments.     

Intensive sequential chemotherapy with repeated blood stem-cell support for untreated poor-prognosis non-Hodgkin's lymphoma

PURPOSE: To demonstrate the feasibility and efficacy of six ambulatory high-dose sequential chemotherapy courses that include three intensified cycles supported by stem-cell infusion in high-risk and high-intermediate-risk untreated non-Hodgkin's lymphoma (NHL) patients. PATIENTS AND METHODS: A pilot nonrandomized study included 20 untreated patients aged less than 60 years with aggressive histologically identified NHL and two or three adverse-prognosis criteria (International Index). Patients received an ambulatory regimen with high-dose chemotherapy supported by granulocyte colony-stimulating factor (G-CSF) and repeated peripheral-blood stem-cell (PBSC) infusion. The median age was 39 years (range, 20 to 59), with 13 men and seven women. Chemotherapy consisted of one cycle every 21 days for a total of six cycles. The first three cycles (A1, A2, and A3) consisted of cyclophosphamide (Cy) 3,000 mg/m2, doxorubicin (Doxo) 75 mg/m2, and vincristine 2 mg (plus corticosteroids). The last three cycles (B4, B5, and B6) consisted of the same drug combination plus etoposide 300 mg/m2 and cisplatin 100 mg/m2. For an expected duration of 18 weeks, the projected dose-intensity was 25 mg/m2/wk for Doxo and 1,000 mg/m2/wk for Cy. G-CSF 300 micrograms was administered from day 6 following each cycle until neutrophil reconstitution. Two aphereses were performed at approximately day 13 after each A cycle, and PBSCs were injected at day 4 of each B cycle. Radiotherapy on tumor masses > or = 5 cm was scheduled after completion of the last cycle. RESULTS: The median duration of grade 4 neutropenia was 1 day (range, 0 to 7) for each A cycle and 4 days (range, 1 to 10) for each B cycle (P = .02). The median duration of grade 4 thrombopenia was 0 days (range, 0 to 8) for each A cycle and 6 days (range, 1 to 21) for each B cycle (P < .001). Hospitalization for febrile neutropenia was required for 18% and 44% of patients during cycles A and B, respectively (P < .01). Only three patients did not complete the protocol: one due to emergency surgery after cycle B4, one who died after cycle B5 from interstitial pneumonia, and one with delayed hematologic reconstitution after cycle B4. Chemotherapy delivery was optimal (median actual relative dose-intensity, 97%; range, 66 to 100). The median total dose administered over 18 weeks was 18,000 mg Cy (range, 12,000 to 18,000), 450 mg Doxo (range, 300 to 450), 900 mg etoposide (range, 300 to 900), and 300 mg cisplatin (range, 100 to 300). Evaluation of response after six courses showed 13 complete remissions ([CRs] 65%), four partial remissions (PRs), two nonresponses (NRs), and one toxic death. With a median follow-up period of 25 months (range, 16 to 43), 15 patients are alive, with 12 in continuous first CR; five patients relapsed (four of four PRs and one of 13 CRs). Two-year survival and failure-free survival (FFS) rates are 73% and 56%, respectively. The disease-free survival (DFS) rate for the CRs is 86%. CONCLUSION: PBSC support contributes to the feasibility of first-line, very-high-dose, ambulatory chemotherapy delivery in poor-risk NHL and is associated with a high rate of remission and FFS.     

Laparoscopic jejunostomy with an 18-mm trocar

BACKGROUND: Aspirin intolerance manifested as bronchospasm or urticaria/angioedema has been observed since the beginning of this century. OBJECTIVE: To report a novel case of intolerance to aspirin ingestion. METHODS: Case report; routine skin testing; pulmonary function testing; aspirin challenge. RESULTS: A 30-year-old man with a history of left ocular trauma at the age of 10 noted a 3-year history of left periorbital angioedema after aspirin but not other nonsteroidal anti-inflammatory drugs. Incremental oral aspirin challenge resulted in this unilateral symptomatology at a dose of 673 mg. CONCLUSION: To the best of our knowledge, this is the first reported case of unilateral periorbital edema following aspirin ingestion.     

Energy Levels of Neutral Platinum

All known energy levels of neutral platinum (Pt I) are presented, including 119 new levels based on analysis of recent comprehensive observations of the spectrum. These results are taken from a detailed analysis of the spectrum to be published in Journal de Physique II.     

Protein engineering of cytochrome c by semisynthesis: substitutions at Glutamic acid 66

We have used protein semisynthesis to prepare four analoguesof horse cytochrome c, in which the glutamic acid residue atposition 66 has been removed and replaced by norvaline, glutamine,lysine and, as a methodological control, glutamic acid. Thisresidue is quite strongly conserved in mitochondrial cytochromec, and forms part of a cluster of acidic residues that occursin all cytochromes c but whose function is obscure. Comparativestudies of the physical and biochemical properties of the analogueshave now disclosed two specific roles for Glu⁶⁶ in the protein.It contributes significantly to the stabilization of the activeconformation of the protein, probably by salt bridge formation,and it appears to participate in the redox-state-dependent ATP-bindingsite of cytochrome c. Our results also support two general viewsof the role of surface charged residues in cytochrome c, namelythat their disposition influences both redox potential, throughthe electrostatic field felt at the redox centre, and the kineticsof electron transfer, through the dipole moment they generate.     

A phase II study of interleukin-2 in 49 patients with relapsed or refractory acute leukemia

Two monoclonal antibodies (mAb) within cluster M4 of the myeloid section of the Second International Swine CD Workshop, C4 (No. 144) and PM18-7 (No. 192), showed reactivity with thymocytes and among cells of myelomonocytic origin with mature macrophages but not with monocytes and granulocytes. Both mAb recognize a protein showing two bands of 205 kDa and 130 kDa under both reducing and non-reducing conditions. Although epitope mapping with these mAb could not be performed, this cluster received the SWC9 designation.