Effect of processing parameters on the mechano-chemical synthesis of nano crystalline Mo-Cu/Al2O3 composite

In this study, molybdenum-copper/alumina nano composite was synthesized with mechano-chemical method using high energy planetary ball milling. The molybdenum oxide, copper oxide and aluminum powder were used as starting materials and reaction appeared to occur through a rapid combustion reaction process. The evaluation of powder particles after different milling times was studied by X-ray diffraction (XRD), differential thermal analysis/thermogravimetric (DTA/TG) and scanning electron microscopy (SEM). XRD results show that with increasing milling time at ambient temperature the peak intensities of powders decreases and significant peak broadening due to decrease in the size of crystallites observed. As a result, after 100 h milling time a molybdenum-copper/alumina metal matrix nanocomposite was formed which matrix had a crystallite size of about 42  nm for cu, calculated from Williamson-Hall equation. In fact by increasing the milling time after reduction of metal oxides, molybdenum dissolves in copper matrix and supersaturated Cu(Mo) solid solution with a homogenous distribution of nano-sized Al2O3 as reinforcement materials was formed. The thermal analysis curves of 10 minutes milled sample shows some peaks related to reduction of copper and molybdenum oxide with aluminum. In addition the small endothermic peak at 650 °C observed from DTA curve is due to the melting of remaining Al

Human Leukocyte Antigens (HLA) Associated with Selective IgA Deficiency in Iran and Sweden

Selective IgA deficiency (IgAD) (serum IgA concentration o

Normal Range Determination of Lymphocytes Subsets in Normal Adults in Iran

Immunophenotyping of lymphocytes is very essential for evaluation of immune system. Due  to  the  effect  of  environmental  factors  and  ethnical diversity on  immune  system, establishment of an internal normal range of lymphocyte subsets is a necessity for each population.  The  aim  of  this  study  was  to  determine  the  normal  range  of  T  and  B lymphocytes, and NK cells in normal Iranian adults. Two hundred and thirty three Iranian normal adult volunteers took part in this study. Complete Blood Count (CBC) was performed for them with Sysmex (KX21) and cells with CD3, CD4, CD8, CD19 and CD16/56  surface markers were simultaneously detected by flow cytometry method  with FACstar system. Their percentile and absolute count  were determined. The  volunteers  were  150  male  and  83  female.  Mean  percentages  of  lymphocyte subpopulation were: CD3 (67.66 ±7.76), CD19 (14.41±5.09), CD4 (39.22±6.7), CD8 (25.42±5.4) and CD16/56 (10.14±6.42). Also, their mean absolute count of lymphocyte bearing CD3, CD19, CD4 and CD8 were 1,504±505/µl, 332±186/µl, 827±313/µl and 522±185/µl, respectively. Our results are comparable with similar Asian results from other Asian population, but are different from European population, we therefore conclude that it is necessary for each laboratory to establish an internal normal range for the lymphocytes bearing above- mentioned markers

Effect of Anti-Epileptic Drugs on Serum Level of IgG Subclasses

Objective: There are some controversial studies on effects of anti-epileptic drugs (AEDs) on serum IgG subclasses; however, the role of these medications is still unclear. The aim of this study was evaluation the effects of anti-epileptic drugs on serum concentration of IgG and its subclasses. Methods: Serum IgG and IgG subclasses of 61 newly diagnosed epileptic patients were measured at the beginning of monotherapy with carbamazepine, sodium valproate, and phenobarbital, and 6 months later. Measurement of IgG and its subclasses was performed using nephlometry and ELISA techniques, respectively. Findings: Reduction of at least one IgG subclass was found in 6 patients 6 months after treatment with AEDs. Among 27 patients receiving carbamazepine, decrease in at least one serum IgG subclass level was found in 5 patients. Among 20 patients using sodium valproate, only one patient showed decrease in IgG2 subclass. None of the 14 patients using phenobarbital revealed significant decrease in IgG subclasses. No infection was seen in the patients with reduction of subclasses. Conclusion: Although in our study, children with selective IgG subclass deficiency were asymptomatic, assessment of serum immunoglobulin levels could be recommended at starting the administration of AEDs and in serial intervals afterward in epileptic patients

B-cell-T-cell activation and interaction in common variable immunodeficiency

Common variable immunodeficiency (CVID) is a heterogeneous group of disorders, characterized by hypogammaglobulinemia and normal or low numbers of B cells, which predispose patients to recurrent infections. Peripheral blood mononuclear cells from 19 patients with CVID, and age- and sex-matched controls, were subjected to an in vitro assay of B-cell-T-cell activation and interaction, using anti-immunoglobulin (Ig)-D conjugated to dextran (alpha-delta-dex), as a polyclonal T independent type 2 antigen mimic, with and without anti-CD3/anti-CD28, as polyclonal T-cell stimuli. Stimulation of lymphocytes with either anti-CD3 or anti-CD3 plus anti-CD28 induced T-cell activation and proliferation in CVID patients who were similar to age- and sex-matched controls, but B cells of patients were significantly less activated when peripheral blood mononuclear cells were stimulated with polyclonal T-cell agonists alone. Comparison of CD86 expression in the patients with matched controls revealed that patients had low B-cell activation in response to T-cell stimuli (bystander T-cell help). In conclusion, this sample of CVID patients exhibits a defect of T-cell "help" to B cells, and/or B-cell response to T-cell hel

Genetic Analysis of a Cohort of 275 Patients with Hyper-IgE Syndromes and/or Chronic Mucocutaneous Candidiasis

Hyper-IgE syndromes and chronic mucocutaneous candidiasis constitute rare primary immunodeficiency syndromes with an overlapping clinical phenotype. In recent years, a growing number of underlying genetic defects have been identified. To characterize the underlying genetic defects in a large international cohort of 275 patients, of whom 211 had been clinically diagnosed with hyper-IgE syndrome and 64 with chronic mucocutaneous candidiasis, targeted panel sequencing was performed, relying on Agilent HaloPlex and Illumina MiSeq technologies. The targeted panel sequencing approach allowed us to identify 87 (32 novel and 55 previously described) mutations in 78 patients, which generated a diagnostic success rate of 28.4%. Specifically, mutations in DOCK8 (26 patients), STAT3 (21), STAT1 (15), CARD9 (6), AIRE (3), IL17RA (2), SPINK5 (3), ZNF341 (2), CARMIL2/RLTPR (1), IL12RB1 (1), and WAS (1) have been detected. The most common clinical findings in this cohort were elevated IgE (81.5%), eczema (71.7%), and eosinophilia (62.9%). Regarding infections, 54.7% of patients had a history of radiologically proven pneumonia, and 28.3% have had other serious infections. History of fungal infection was noted in 53% of cases and skin abscesses in 52.9%. Skeletal or dental abnormalities were observed in 46.2% of patients with a characteristic face being the most commonly reported feature (23.1%), followed by retained primary teeth in 18.9% of patients. Targeted panel sequencing provides a cost-effective first-line genetic screening method which allows for the identification of mutations also in patients with atypical clinical presentations and should be routinely implemented in referral centers

Structure and properties of polydiacetylene-containing peptide amphiphile fibres

Contains fulltext : 83167.pdf (publisher's version ) (Open Access)Radboud Universiteit Nijmegen, 10 februari 2011Promotor : Hest, J.C.M. van Co-promotor : Lowik, D.W.P.M.184 p