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Gas adsorption is widely used in air pollution control, with mainly activated carbon and zeolites used as adsorbents. Although physical and chemisorption can be used, most air pollution application...

International audience; The in situ analysis of industrial processes, mostly conducted in opaque equipment is difficult. Whereas previously the positron emission technique was successfully applied to study the flow and mixing in gas-solid and liquid-solid systems using radio-active tracer particles, research on imaging a radio- active tracer gas is scarce. The present paper demonstrates the use of a fully three-dimensional (3D) Positron Emission Tomography (PET) in imaging the adsorption of 11CO2 tracer gas, while validating the measurement by conventional exit gas analysis. It will be demonstrated that PET can be used to measure the kinetics of high-pressure CO2 adsorption in situ, including the essential breakthrough and mass transfer zone characteristics. Such high-pressure operation is characteristic of pre-combustion CO2 capturing processes. It is expected that this work will foster further studies of gas-solid systems of adsorption, gas-solid catalysis, gas-solid hydrodynamics, and processes where the gas-solidinteraction is of primary importance.

Thalidomide is used to treat human immunodeficiency virus (HIV)-associated conditions, including aphthous ulcers and wasting syndrome. The safety, tolerability, and pharmacokinetics of a formulation of thalidomide with improved bioavailability in HIV-infected persons was examined in a placebo-controlled, dose-escalating phase 1 study. Subjects with CD4 cell counts of 200-500 cells/mm(3) were enrolled and randomized 3:1 in groups of 12 to receive 50, 100, or 150 mg of thalidomide or matching placebo. Two subjects who received 150 mg of drug and 2 subjects assigned placebo experienced dose-limiting toxicity. Concentrations of thalidomide in the blood increased with escalating dose, but the time to maximum concentration and clearance did not differ across dose cohorts. Previous suggestions of autoinduction of drug metabolism were not confirmed by this study. At the doses studied, thalidomide was tolerated well and had linear pharmacokinetics.

OBJECTIVE To compare the virologic activity of continued lamivudine (3TC) versus a switch to delavirdine (DLV) when initiating protease inhibitor therapy in nucleoside-experienced patients. DESIGN Randomized, open-label, multi-center study. SETTING Adult AIDS clinical trials units. PATIENTS Protease and non-nucleoside reverse transcriptase inhibitor-naive patients who had received 3TC plus zidovudine (ZDV), stavudine (d4T), or didanosine (ddl) for at least 24 weeks. INTERVENTIONS Patients with plasma HIV-1 RNA levels > 500 copies/ml who previously received d4T + 3TC or ddI + 3TC were randomized to ZDV + 3TC + indinavir (IDV) or ZDV + DLV + IDV. MAIN OUTCOME MEASURES Primary endpoints were the proportion of patients with plasma HIV-1 RNA levels < or = 200 copies/ml at 24 weeks, and occurrence of serious adverse events. The proportion of patients with plasma HIV-1 RNA levels < or = 200 copies/ml at week 48 was a secondary endpoint. RESULTS At week 24, 58% of subjects in the ZDV + 3TC + IDV arm and 73% in the ZDV + DLV + IDV arm had plasma HIV-1 RNA levels < or = 200 copies/ml (P = 0.29). At week 48, plasma HIV-1 RNA levels were < or = 200 copies/ml in 48% and 83%, respectively (P = 0.007). Rash and hyperbilirubinemia occurred more frequently in the DLV arm than in the 3TC arm. Steady-state plasma IDV levels were higher among patients in the DLV arm as compared with the 3TC arm. CONCLUSIONS Substituting DLV for 3TC when adding IDV improved virologic outcome in nucleoside-experienced patients. This result might be explained, in part, by the positive effect of DLV on IDV pharmacokinetics.

Granulocyte colony-stimulating factor (r-met Hu G-CSF; filgrastim; 10 microgram/kg/day for 7 days) was used to mobilize CD34+stem cells into the peripheral blood of human immunodeficiency virus type 1 (HIV-1)-infected individuals and a group of HIV-1-uninfected donors as a measure of immunologic reserve in HIV-1-infected people. G-CSF mobilized CD34+ cells of HIV-1-infected individuals with cell counts500 CD4+ cells/mm3, as well as in HIV-1-uninfected donors. In contrast, CD34 cell mobilization was significantly blunted in HIV-1-infected individuals with cell counts500 CD4+ cells/mm3 (200 cell days vs.650 cell days, P.0005, compared with the500 CD4+ cell cohort). At least 1.75x10(7) CD34 cells were harvested by leukapheresis from patients in each study cohort. CD34+ cell viability and the ability to differentiate precursor cells into myeloid and erythroid progenitor cells were not affected by HIV-1 infection.

Objective: To study the antiviral activity of lamivudine (3TC) plus zidovudine (ZDV), didanosine (ddl), or stavudine (d4T). Design: Randomized, placebo-controlled, partially double-blinded multicenter study. Setting: Adult AIDS Clinical Trials Units. Patients: Treatment-naive HIV-infected adults with 200-600 x 10 6 CD4 T lymphocytes/l. Interventions: Patients were openly randomized to a d4T or a ddl limb, then randomized in a blinded manner to receive: d4T (80 mg/day), d4T plus 3TC (300 mg/day), or ZDV (600 mg/day) plus 3TC, with matching placebos; or ddl (400 mg/day), ddl plus 3TC (300 mg/day), or ZDV (600 mg/day) plus 3TC, with matching placebos. After 24 weeks 3TC was added for patients assigned to the monotherapy arms. Main outcome measure: The reduction in plasma HIV-1 RNA level at weeks 24 and 48. Results: Two hundred ninety-nine patients were enrolled. After 24 weeks the mean reduction in plasma HIV-1 RNA copies/ml from baseline was 0.49 log 10 (d4T monotherapy) versus 1.03 log 10 (d4T plus 3TC; P = 0.001), and 0.68 log 10 (ddl monotherapy) versus 0.82 log 10 (ddl plus 3TC; P > 0.22). After 48 weeks the mean reduction was 1.08 log 10 (D4T plus 3TC) versus 1.01 log 10 (ZDV plus 3TC) in the d4T limb (P = 0.66), and 0.94 log 10 (ddl plus 3TC) versus 0.88 log 10 (ZDV plus 3TC; P = 0.70) in the ddl limb. Conclusions: 3TC added significantly to the virologic effects of d4T, but not ddl, in treatment-naive patients. 3TC plus d4T produced virologic changes comparable to those of 3TC plus ZDV. These results support the use of 3TC with either ZDV or d4T as a component of initial combination antiretroviral therapy.

The potential role of human immunodeficiency virus type 1 (HIV-1)-specific immune responses in controlling viral replication in vivo has stimulated interest in enhancing virus-specific immunity by vaccinating infected individuals with HIV-1 or its components. These studies were undertaken to define patient populations most likely to respond to vaccination, with the induction of novel HIV-1-specific cellular immune responses, and to compare the safety and immunogenicity of several candidate recombinant HIV-1 envelope vaccines and adjuvants. New lymphoproliferative responses (LPRs) developed in30% of vaccine recipients. LPRs were elicited primarily in study participants with a CD4 cell count350 cells/mm(3) and were usually strain restricted. Responders tended to be more likely than nonresponders to have an undetectable level of HIV-1 RNA at baseline (P=.067). Induction of new cellular immune responses by HIV-1 envelope vaccines is a function of the immunologic stage of disease and baseline plasma HIV-1 RNA level and exhibits considerable vaccine strain specificity.

Electron microscopy of thin sections of salivary glands from wheat striate mosaic virus (WSMV)-infected leafhoppers, Endria inimica (Say), showed for the first time the presence of rhabdovirus particles in the leafhopper vector. These virus particles looked similar to those that have been observed in WSMV-infected wheat. The virions were found in the nuclei of infected cells both in well-defined intranuclear inclusions and in spaces between the inner and outer nuclear membranes. Bundles of particles were also seen in the cytoplasm close to infected nuclei. No particles were found in leafhoppers reared on virus-free wheat.