Local Response to Microneedle-Based Influenza Immunization in the Skin

Microneedle patches (MN) provide a novel method of vaccine delivery to the skin with the objective of targeting the large network of resident antigen-presenting cells to induce an efficient immune response. Our previous reports demonstrated that cutaneous delivery of inactivated influenza virus-coated MN to mice protects against lethal infection. Protection is correlated with sustained levels of anti-influenza virus serum antibodies, hemagglutination inhibition titers, and robust cellular responses that are often stronger than those generated by intramuscular vaccination. Here we dissect the early events occurring in murine skin after microneedle delivery of inactivated influenza virus. We demonstrate correlation of immunization against influenza virus with a local increase of cytokines important for recruitment of neutrophils, monocytes and dendritic cells at the site of immunization. We also observed prolonged antigen deposition, and migration of matured dendritic cells bearing influenza virus antigen from the skin

Effects of immunomodulatory drugs on TNF-α and IL-12 production by purified epidermal langerhans cells and peritoneal macrophages

<p>Abstract</p> <p>Background</p> <p>Langerhans cells constitute a special subset of immature dendritic cells localized in the epidermis that play a key role in the skin's immune response. The production of cytokines is a key event in both the initiation and the regulation of immune responses, and different drugs can be used to remove or modify their production by DC and, therefore, alter immune responses in a broad spectrum of diseases, mainly in human inflammatory and autoimmune diseases. In the present study, we examined the effects of prednisone, thalidomide, cyclosporine A, and amitriptyline, drugs used in a variety of clinical conditions, on the production of TNF-α, IL-10, and IL-12 by purified epidermal Langerhans cells and peritoneal macrophages in BALB/c mice.</p> <p>Findings</p> <p>All drugs inhibited TNF-α production by Langerhans cells after 36 hours of treatment at two different concentrations, while prednisone and thalidomide decreased IL-12 secretion significantly, amitriptyline caused a less pronounced reduction and cyclosporine A had no effect. Additionally, TNF-α and IL-12 production by macrophages decreased, but IL-10 levels were unchanged after all treatments.</p> <p>Conclusions</p> <p>Our results demonstrate that these drugs modulate the immune response by regulating pro-inflammatory cytokine production by purified epidermal Langerhans cells and peritoneal macrophages, indicating that these cells are important targets for immunosuppression in various clinical settings.</p

Very Small Embryonic-Like Stem Cells Purified from Umbilical Cord Blood Lack Stem Cell Characteristics

Very small embryonic-like (VSEL) cells have been described as putatively pluripotent stem cells present in murine bone marrow and human umbilical cord blood (hUCB) and as such are of high potential interest for regenerative medicine. However, there remain some questions concerning the precise identity and properties of VSEL cells, particularly those derived from hUCB. For this reason, we have carried out an extensive characterisation of purified populations of VSEL cells from a large number of UCB samples. Consistent with a previous report, we find that VSEL cells are CXCR4+, have a high density, are indeed significantly smaller than HSC and have an extremely high nuclear/cytoplasmic ratio. Their nucleoplasm is unstructured and stains strongly with Hoechst 33342. A comprehensive FACS screen for surface markers characteristic of embryonic, mesenchymal, neuronal or hematopoietic stem cells revealed negligible expression on VSEL cells. These cells failed to expand in vitro under a wide range of culture conditions known to support embryonic or adult stem cell types and a microarray analysis revealed the transcriptional profile of VSEL cells to be clearly distinct both from well-defined populations of pluripotent and adult stem cells and from the mature hematopoietic lineages. Finally, we detected an aneuploid karyotype in the majority of purified VSEL cells by fluorescence in situ hybridisation. These data support neither an embryonic nor an adult stem cell like phenotype, suggesting rather that hUCB VSEL cells are an aberrant and inactive population that is not comparable to murine VSEL cells

Assessing the potential and limitations of membrane-based technologies for the treatment of oilfield produced water

In this study, the recent advances in standalone membrane technologies were investigated for produced water treatment and reclamation. The effect of operating parameters (i.e. temperature, flow rate, velocity, and pH) on membrane fouling were studied in detail. Results showed that microfiltration suffered severe fouling from suspended particles and flux deterioration reacheed 90 % in less than 1 h. Ultrafiltration showed enhanced removal of oil up to 95 % however, membrane hydrophilicity needs to be increased and the suspended particulates should be minimized to sustain operation. Nanofiltration was more prone to fouling with maximum oil removal 99 % and removal of 10 % to 20 % of dissolved solids. Reverse osmosis (RO) performance decreased rapidly against mild salts and oil concentrations in the range of 2000 ppm salts and 150 ppm crude oil and was therefore not suitable for standalone. Developed technologies such as membrane distillation (MD) and forward osmosis (FO) showed remarkable operation stability against high concentrations of oil and salts (1000 ppm crude oil and up to 150,000 ppm of salts). Hybridization of nanofiltration or RO with MD or FO processes showed promising results in pilot tests

Economic evaluation of aromatics production, a case study for financial model application in petrochemical projects

Economics is the engine that drives industry. For complete understanding of project economics four major items must be discussed; capital requirements, operating expenses, cash flow and profitability measures. Petrochemicals in general are compounds and polymers derived directly or indirectly from petroleum. C6–C8 aromatics are petrochemical intermediates that include benzene, toluene and xylenes. This research work aims to execute a financial model template using MICROSOFT EXCEL PROGRAM which can be applied on any industry to check its profitability. Two configurations for aromatics production had been considered as a case study for model application, Configuration I for the production of benzene, toluene and xylenes and Configuration II for the production of benzene and para xylene only based on 3 million tons of straight run naphtha feedstock. In addition, the economic effect of the integration between Configuration II and MIDOR refinery had been studied. The designed and initiated financial model performed in this paper is applied on a real and existing petrochemical project to check its validation. The economic indicators calculated using the initiated financial model were found to match with the actual status of the project. The research resulted in; Configuration I and II are not profitable under the mentioned basis. The integration between Configuration II and MIDOR refinery is more profitable than the standalone one. Configurations I and II shall be feasible if the quantity of naphtha feedstock increases to 70,000 and 5500 thousand tons per year respectively. Configurations I and II shall be feasible if the discount in naphtha feedstock price reaches to 9% and 4.5% respectively

Ontogénie des lymphocytes T chez l'homme, en particulier entre les 10e et 20e semaines de vie foetale

International audienc

Corrosion study of carbon steel in CO 2 loaded solution of N-methyldiethanolamine and L-arginine mixtures

This study presents an electrochemical corrosion investigation of carbon steel in blends of methyldiethanolamine (MDEA) and arginine (ARG) at different molar concentrations and solvent proportions. The effects of three main parameters which are CO 2 partial pressure, solution temperature and MDEA/ARG proportions ratio were studied. The selected temperatures range varied from 293 to 323 K and the CO 2 partial pressure was in the range of 49-98 kPa. The results showed that the corrosion rate increased with increased CO 2 partial pressure and solution temperature. However, when ARG was added to MDEA, it was found that ARG acts as an inhibitor, the higher ARG fraction in the mixture, the more inhibition effect was observed. SEM, XRD, and XPS techniques were used to characterize the corroded surfaces; analysis of the corrosion products of the specimen surface confirmed the formation of FeCO 3 protective layer.This paper was made possible by an NPRP Grant # 7-1154-2-433 from the Qatar National Research Fund (a member of Qatar Foundation).Scopu

Assessing the fouling behavior of PTFE membrane in air-gap membrane distillation against oil-in-brine stabilized emulsions

Abstract Understanding the fouling behavior in membrane operations is crucial for designing an effective treatment sequence. The membrane materials, feed characteristics, and operating conditions affect the fouling behavior. In this study, the fouling behavior of polytetrafluoroethylene (PTFE) membrane in membrane distillation was assessed after the treatment of oil-in-brine stabilized emulsions. Membrane backwash by water in membrane distillation partially restored the membrane’s initial condition and eliminated salt fouling. Moreover, the effect of feed pretreatment by ultrafiltration on the fouling of the subsequent PTFE membrane was investigated. Remarkable improvements in salt rejection (> 98.5%) and oil rejection (> 96%) were observed for the hybrid system. Extensive characterizations were carried out to evaluate the fouling behavior. Surface morphology and elemental analysis revealed the nature of foulants. Fourier transform infrared spectroscopy was utilized to study the change in the surface chemistry of the membranes after being subjected to the oily brine feed. No peak shifting was observed indicating no chemical bonding between the organic contaminants and the membrane surface. Further elaboration of the results was achieved by measuring the mechanical stability and contact angle of the membranes. Reduction in the mechanical properties and water contact angle of the membranes was observed after fouling and wetting. Results indicated that ultrafiltration was an effective pretreatment process for membrane distillation using PTFE membrane. However, more unit operations should be incorporated to enhance the membranes’ integrity

“Increased percentage of activated Ia+ T lymphocytes in peripheral blood of neonates following exchange blood transfusion”.

The expression of Ia-like antigens in peripheral blood T lymphocytes from newborns receiving postnatal total blood exchange was analyzed. A significantly increased percentage of Ia-positive T lymphocytes (Ia+ T cells) was observed 2 days after postnatal transfusion with total blood in comparison to data observed on Days 0, 5, and 15. Ia+ T cells were also significantly higher than in normal control newborns tested in the same period. When newborns received the blood exchange with irradiated total blood or with leukocyte-depleted blood, no increase in Ia+ T cells was observed and the percentage of these cells remained in the normal range (1-7%) on all the days tested (0, 2, 5, 15 days). For easy identification of the origin of Ia+ T cells, sex-incompatible blood was used for exchange, and a karyotype analysis was carried out for the detection of the Y chromosome on Ia+ T cells separated from peripheral blood on Day 2 and then cultured with interleukin 2 (IL-2) for 48 hr. It was thus established that Ia+ T cells were not of donor origin. Simultaneously with the expression of Ia-like antigens, host T cells also carried the interleukin-2 receptor (TAC). An allogeneic response, comparable to a host-versus-graft reaction, was probably responsible for the activation of T cells 2 days after total blood exchange in newborns