20 research outputs found
A general perspective of the characterization and quantification of nanoparticles: Imaging, spectroscopic, and separation techniques
This article gives an overview of the different techniques used to identify, characterize, and quantify engineered nanoparticles (ENPs). The state-of-the-art of the field is summarized, and the different characterization techniques have been grouped according to the information they can provide. In addition, some selected applications are highlighted for each technique. The classification of the techniques has been carried out according to the main physical and chemical properties of the nanoparticles such as morphology, size, polydispersity characteristics, structural information, and elemental composition. Microscopy techniques including optical, electron and X-ray microscopy, and separation techniques with and without hyphenated detection systems are discussed. For each of these groups, a brief description of the techniques, specific features, and concepts, as well as several examples, are described.Junta de Andalucía FQM-5974CEI-Biotic Granada CEI2013- MP-1
Resolution of disseminated fusariosis in a child with acute leukemia treated with combined antifungal therapy: a case report
<p>Abstract</p> <p>Background</p> <p><it>Fusarium </it>spp. is being isolated with increasing frequency as a pathogen in oncohematologic patients. Caspofungin and amphotericin B have been reported to have synergistic activity against <it>Fusarium </it>spp.</p> <p>Case presentation</p> <p>We herein report a case of disseminated fusariosis diagnosed by chest CT scan and positive blood cultures to <it>Fusarium </it>spp. Because the patient's clinical condition deteriorated, CRP levels increased, and blood cultures continued to yield <it>Fusarium </it>spp. despite liposomal amphotericin B monotherapy up to 5 mg/kg daily, treatment with caspofungin was added. Within 2 weeks of onset of combined antifungal therapy, the chest CT scan demonstrated a progressive resolution of the pulmonary lesions. Upon discontinuation of intravenous antifungals, the patient received suppressive therapy with oral voriconazole. Three months later, a chest CT scan showed no abnormalities. Twenty-five months after discontinuation of all antifungal therapy, the patient remains in complete remission of her neoplastic disease with no signs of clinical activity of the <it>Fusarium </it>infection.</p> <p>Conclusion</p> <p>This is the first description of successful treatment of disseminated fusariosis in a pediatric patient with acute lymphoblastic leukemia with caspofungin and amphotericin B followed by oral suppressive therapy with voriconazole.</p
A General Perspective of the Characterization and Quantification of Nanoparticles: Imaging, Spectroscopic, and Separation Techniques
Antiinflammatory Therapy with Canakinumab for Atherosclerotic Disease
Background: Experimental and clinical data suggest that reducing inflammation without affecting lipid levels may reduce the risk of cardiovascular disease. Yet, the inflammatory hypothesis of atherothrombosis has remained unproved. Methods: We conducted a randomized, double-blind trial of canakinumab, a therapeutic monoclonal antibody targeting interleukin-1β, involving 10,061 patients with previous myocardial infarction and a high-sensitivity C-reactive protein level of 2 mg or more per liter. The trial compared three doses of canakinumab (50 mg, 150 mg, and 300 mg, administered subcutaneously every 3 months) with placebo. The primary efficacy end point was nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death. RESULTS: At 48 months, the median reduction from baseline in the high-sensitivity C-reactive protein level was 26 percentage points greater in the group that received the 50-mg dose of canakinumab, 37 percentage points greater in the 150-mg group, and 41 percentage points greater in the 300-mg group than in the placebo group. Canakinumab did not reduce lipid levels from baseline. At a median follow-up of 3.7 years, the incidence rate for the primary end point was 4.50 events per 100 person-years in the placebo group, 4.11 events per 100 person-years in the 50-mg group, 3.86 events per 100 person-years in the 150-mg group, and 3.90 events per 100 person-years in the 300-mg group. The hazard ratios as compared with placebo were as follows: in the 50-mg group, 0.93 (95% confidence interval [CI], 0.80 to 1.07; P = 0.30); in the 150-mg group, 0.85 (95% CI, 0.74 to 0.98; P = 0.021); and in the 300-mg group, 0.86 (95% CI, 0.75 to 0.99; P = 0.031). The 150-mg dose, but not the other doses, met the prespecified multiplicity-adjusted threshold for statistical significance for the primary end point and the secondary end point that additionally included hospitalization for unstable angina that led to urgent revascularization (hazard ratio vs. placebo, 0.83; 95% CI, 0.73 to 0.95; P = 0.005). Canakinumab was associated with a higher incidence of fatal infection than was placebo. There was no significant difference in all-cause mortality (hazard ratio for all canakinumab doses vs. placebo, 0.94; 95% CI, 0.83 to 1.06; P = 0.31). Conclusions: Antiinflammatory therapy targeting the interleukin-1β innate immunity pathway with canakinumab at a dose of 150 mg every 3 months led to a significantly lower rate of recurrent cardiovascular events than placebo, independent of lipid-level lowering. (Funded by Novartis; CANTOS ClinicalTrials.gov number, NCT01327846.
Thermoresponsive gold polymer nanohybrids with a tunable cross-linked meo 2 ma polymer shell
Gold nanoparticles (AuNPs) are functionalized with a thermoresponsive polymer shell of a cross-linked poly(2-(2-methoxyethoxy)ethyl methacrylate) (P(MEO 2 MA)). To provide a covalent attachment of the polymer to the NP surface, AuNPs are fi rst modifi ed using butanoic acid to develop the encapsulation with the biocompatible thermoresponsive polymer formed by free-radical precipitation polymerization. Both the MEO 2 MA concentration and the shell cross-linking density can be varied and, in turn, the thickness and the shells' free volume can be fi ne-tuned. By downscaling the size of the polymeric shell, the lower critical solution temperature (LCST) is decreased. The LCST in the nanohybrids changes from 19.1 to 25.6 °C when increasing the MEO 2 MA content; it reaches almost 26 °C for P(MEO 2 MA) (bulk). The maximum decrease in the volume of the nanohybrids is around 40%, resulting in a modifi cation of the light scattering properties of the system and causing a change in the turbidity of the gel network. The sizes of the nanohybrids are characterized using both transmission electron microscopy and dynamic light scattering measurements. Optical properties of the colloidal systems are determined using the derived count rate measurements as an alternative to absorbance or transmittance measurements, confi rming the colloidal stability of the nanohybrid systems.Peer Reviewe