Effect of dimethylamine on the gas phase sulfuric acid concentration measured by Chemical Ionization Mass Spectrometry.

Sulfuric acid is widely recognized as a very important substance driving atmospheric aerosol nucleation. Based on quantum chemical calculations it has been suggested that the quantitative detection of gas phase sulfuric acid (H2SO4) by use of Chemical Ionization Mass Spectrometry (CIMS) could be biased in the presence of gas phase amines such as dimethylamine (DMA). An experiment (CLOUD7 campaign) was set up at the CLOUD (Cosmics Leaving OUtdoor Droplets) chamber to investigate the quantitative detection of H2SO4 in the presence of dimethylamine by CIMS at atmospherically relevant concentrations. For the first time in the CLOUD experiment, the monomer sulfuric acid concentration was measured by a CIMS and by two CI-APi-TOF (Chemical Ionization-Atmospheric Pressure interface-Time Of Flight) mass spectrometers. In addition, neutral sulfuric acid clusters were measured with the CI-APi-TOFs. The CLOUD7 measurements show that in the presence of dimethylamine (<5 to 70 pptv) the sulfuric acid monomer measured by the CIMS represents only a fraction of the total H2SO4, contained in the monomer and the clusters that is available for particle growth. Although it was found that the addition of dimethylamine dramatically changes the H2SO4 cluster distribution compared to binary (H2SO4-H2O) conditions, the CIMS detection efficiency does not seem to depend substantially on whether an individual H2SO4 monomer is clustered with a DMA molecule. The experimental observations are supported by numerical simulations based on A Self-contained Atmospheric chemistry coDe coupled with a molecular process model (Sulfuric Acid Water NUCleation) operated in the kinetic limit.

Nursing care of children with HIV infection.

Infection with HIV is producing a new population of chronically and terminally ill children. This chapter deals with issues to help in the understanding of both the physical realities and the "experience" of families who live in the shadow of AIDS.

Neuritis óptica luética en pacientes no VIH: revisión a propósito de 2 casos / Syphilitic optic neuritis in non HIV patients: review on 2 cases report

Introduction: Syphilis was an important cause of ocular inflammation during the pre-antibiotic era. Nowadays, its prevalence has clearly diminished and, although there has been an arousal of its manifestations in the Central Nervous System, mostly among HIV (+) patients; ocular compromise, particularly optic neuritis, are still infrequent. Nevertheless, the consequences of a late medical treatment maintain the importance of considering this diagnosis as an option in many clinical scenarios. Method: Review of the actual literature from the experience of two cases we recently treated. Discussion: We present the physiopathology clinical manifestations, diagnosis and treatment of syphilis, specifically its neurological and ocular manifestations in HIV and no HIV patients, discussing whether is necessary to actively search for syphilis in patients consulting with optic neuritis. Conclusion: As VDRL is an accessible exam for the differential diagnostic of syphilis in patients cursing with optic neuritis, we propose to practice it always in every patient, we suspect this pathology.

Introducción: La sífilis fue en la época preantibiótica causa frecuente de inflamación ocular. Actualmente su prevalencia ha disminuido, y si bien hemos visto una recrudescencia de sus manifestaciones en el sistema nervioso central asociada a la enfermedad por VIH, las manifestaciones oculares, particularmente la Neuritis Óptica, siguen siendo muy infrecuentes. Sin embargo, las consecuencias del retraso de tratamiento antibiótico oportuno, obligan al médico a tener presente este diagnóstico en diversos escenarios clínicos. Método: Revisión bibliográfica a partir de la descripción de dos casos que tratamos recientemente. Discusión: Exponemos la fisiopatología, clínica, diagnóstico y tratamiento de la sífilis con consideraciones especiales en sus manifestaciones neurológicas y oftalmológicas, en paciente VIH como no VIH, discutiendo si es necesario buscar activamente la sífilis en casos de Neuritis Óptica. Conclusión: El VDRL como herramienta para realizar el diagnóstico diferencial en un cuadro de Neuritis Óptica es un examen accesible para el clínico, por lo que proponemos solicitarlo de rutina en todo paciente que presente esta patología.

Some further thoughts on adjustment, coping, and bereavement.

Adjusting to and coping with HIV-AIDS is a difficult task. This chapter describes some of the issues surrounding being diagnosed HIV positive, living with HIV, and progressing to AIDS. It also explores bereavement reactions that relatives and friends can experience in dealing with illness and death due to HIV.

Expression of tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) receptors and sensitivity to TRAIL-induced apoptosis in primary B-cell acute lymphoblastic leukaemia cells.

Because tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) (Apo2 ligand) preferentially kills malignant cells while sparing normal cells, it may be therapeutically useful against cancers, including those of haematopoietic origin. Although the activity of TRAIL has been studied in tumour cell lines and in a limited number of different primary tumours, its overall activity in a large number of uniform cases of primary tumours is not known. We therefore studied the activity of TRAIL in 29 primary precursor B-cell acute lymphoblastic leukaemia (ALL) samples. TRAIL was found to have a modest activity as it killed a maximum of 29% of ALL cells within 18 h compared with killing 75% of Jurkat cells. The sensitivity to TRAIL did not correlate with the pattern of TRAIL receptor expression or FLIP expression, as determined by Western blot analysis. The CD40 receptor, which can transduce survival signals in mature malignant B cells, was less frequently expressed on ALL cells, but incubation with an exogenous soluble CD40 ligand trimer did not rescue them from spontaneous apoptosis and did not mediate their resistance to TRAIL. Further, although ALL cells expressed TRAIL protein, they failed to kill target Jurkat cells in a TRAIL-dependent manner. Our data delineate major biological differences between mature and precursor malignant B cells and suggest a limited therapeutic role for TRAIL as a single agent in primary B-cell ALL.

Monocyte enrichment from leukapharesis products for the generation of DCs by plastic adherence, or by positive or negative selection.

BACKGROUND: DCs for use in immunotherapy are frequently generated from peripheral blood monocytes. However, there are different approaches to monocyte enrichment. METHOD: Plastic adherence is a widely used method for the enrichment of monocytes collected in a leukapheresis procedure. Alternatively,monocytes may be enriched by positive selection using magnetic beads coupled to CD14 Abs, or by cell depletion using beads coupled to Abs against CD2 and CD19 to remove non-monocytes. RESULTS: Positive selection resulted in the highest purity of immature DCs (97 +/- 1%), but in a low yield (8 +/- 3%). In contrast, depletion of non-monocytes gave a good yield (21 +/- 6%), but insufficient purity (42 +/- 10%). Conventional adherence procedures resulted in a good yield (25 +/- 5%) and reasonable purity (72 +/- 4%). All three monocyte enrichment procedures resulted in DCs that underwent maturation upon exposure to a combination of lipopolysaccharide and IFN-gamma. These DCs had a typical immune phenotype, they released similar amounts of IL-12, and had the capacity to support MLR. CONCLUSION: Our data provide a basis to choose a monocyte enrichment procedure that favors high purity or a high yield. However, if a manual open system suffices, plastic adherence is a reasonable alternative.