212 research outputs found
Performance of Close Anode Cathodic Protection System Applied to a Plane Metallic Grid
In CP technique the negative shift in cathode potential determines the degree of protection against corrosion. This shift occurs by two mechanisms: the first is depression of cathode potential relative to electrolyte (Remote Anode Systems). The second is elevation of electrolyte potential in the vicinity of cathode relative to electrolyte (Close Anode Systems). These systems are considerably sensitive to anode position because of sharp changes in electrolyte potential with variation of anode location (proximity effect). Our work is to investigate the performance of CP system under conditions of variable anode position, applied to mild steel grid simulating steel reinforced concrete
The Moment Problem in Hypercomplex Systems
This paper is devoted to give the necessary and sufficient conditions guarantees that the product of two generalized moment functions defined in a hypercomplex system L1(Q,m) is also generalized moment function in L1(Q,m) . Also, we prove that a bounded continuous function in a hypercomplex system L1(Q,m) is conditionally positive definite if and only if is generalized moment functions defined in L1(Q,m) . Moreover, we will give the integral representations of a generalized moment functions defined in L1 (Q, m)
High resolution computed tomography and pulmonary function tests in childhood systemic lupus erythematosus and juvenile rheumatoid arthritis
Background: Alveolar and airway injury represent one of the most common features of rheumatological diseases and is believed to have a significant impact on the course of these diseases. Objective: This work aimed at evaluating airway and alveolar involvement in children with systemic lupus erythematosus (SLE) and juvenile rheumatoid arthritis (JRA). Methods: Thirty four children (21 with SLE and 13 with JRA) were assessed by pulmonary function tests (PFTs) namely spirometry and carbon monoxide diffusion capacity (DLCO) in comparison to 10 healthy controls, as well as by plain roentgenography and high resolution computed tomography (HRCT) of the chest. Results: The studied patients had significantly lower mean PFT values as compared to controls. A restrictive pattern of PFTs was more common as it was detected in 62% of patients with SLE and 23% of those with JRA whereas an obstructive pattern was detected in 14% and 8% respectively. Significantly lower FEF 25-75% values were detected in symptomatic patients. Low values of DLCO (less than 80% of predicted) were recorded in 60% of the studied patients. Chest HRCT was abnormal in 68% of studied patients. In SLE, ground glass appearance and pleural irregularity were the most common findings whereas in JRA, bronchial wall thickening, mosaic appearance and air trapping were prominent. Abnormal findings were detected in 5/9 of asymptomatic patients. Conclusion: airway and alveolar abnormalities are frequently encountered in children with SLE (95%) and JRA (85%) even if they are asymptomatic. HRCT and pulmonary function tests including diffusion studies are recommended as useful tools for the diagnosis and early detection of pulmonary involvement in these patients.Keywords: JRA, SLE, HRCT, PFTs, DLCOEgypt J Pediatr Allergy Immunol 2004; 2(1): 8-1
Peptide-Pulsed Dendritic Cells Induce the Hepatitis C Viral Epitope-Specific Responses of Naïve Human T Cells
Hepatitis C virus (HCV) is a major cause of liver disease. Spontaneous resolution of infection is associated with broad, MHC class I- (CD8+) and class II-restricted (CD4+) T cell responses to multiple viral epitopes. Only 20% of patients clear infection spontaneously, however, most develop chronic disease. The response to chemotherapy varies; therapeutic vaccination offers an additional treatment strategy. To date, therapeutic vaccines have demonstrated only limited success in clinical trials. Vector-mediated vaccination with multi-epitope-expressing DNA constructs provides an improved approach. Highly-conserved, HLA-A2-restricted HCV epitopes and HLA-DRB1-restricted immunogenic consensus sequences (ICS, each composed of multiple overlapping and highly conserved epitopes) were predicted using bioinformatics tools and synthesized as peptides. HLA binding activity was determined in competitive binding assays. Immunogenicity and the ability of each peptide to stimulate naïve human T cell recognition and IFN-γ production were assessed in cultures of total PBMCs and in co-cultures composed of peptide-pulsed dendritic cells (DCs) and purified T lymphocytes, cell populations derived from normal blood donors. Essentially all predicted HLA-A2-restricted epitopes and HLA-DRB1-restricted ICS exhibited HLA binding activity and the ability to elicit immune recognition and IFN-γ production by naïve human T cells. The ability of DCs pulsed with these highly-conserved HLA-A2- and -DRB1-restricted peptides to induce naïve human T cell reactivity and IFN-γ production ex vivo demonstrates the potential efficacy of a multi-epitope-based HCV vaccine targeted to dendritic cells
An aggravated trajectory of depression and anxiety co-morbid with hepatitis C: : A 21 to 62 month follow-up study in 61 South Australian outpatients
BACKGROUND: This study aimed to explore the course of depression and anxiety in chronic hepatitis C patients. METHODS: Data were combined from two studies: (1) Hospital Anxiety and Depression Scale (HADS) scores in 395 consecutive Australian outpatients from 2006 to 2010 formed the baseline measurement; and (2) Depression Anxiety Stress Scales (DASS) scores in a survey of a sub-sample of these patients in 2011 formed the follow-up measurement. After converting DASS to HADS scores, changes in symptom scores and rates of case-ness (≥8), and predictors of follow-up symptoms were assessed. RESULTS: Follow-up data were available for 61 patients (70.5% male) whose age ranged from 24.5 to 74.6 years (M=45.6). The time to follow-up ranged from 20.7 to 61.9 months (M=43.8). Baseline rates of depression (32.8%) and anxiety (44.3%) increased to 62.3% and 67.2%, respectively. These findings were confirmed, independent of the conversion, by comparing baseline HADS and follow-up DASS scores with British community norms. Baseline anxiety and younger age predicted depression, while baseline anxiety, high school non-completion, and single relationship status predicted anxiety. CONCLUSION: This study demonstrated a worsening trajectory of depression and anxiety. Further controlled and prospective research in a larger sample is required to confirm these findings
Uncovering the Importance of Selenium in Muscle Disease
A connection between selenium bioavailability and development of muscular
disorders both in humans and livestock has been established for a long time.
With the development of genomics, the function of several selenoproteins was
shown to be involved in muscle activity, including SELENON, which was linked to
an inherited form of myopathy. Development of animal models has helped to dissect
the physiological dysfunction due to mutation in the SELENON gene; however the
molecular activity remains elusive and only recent analysis using both in vivo and
in vitro experiment provided hints toward its function in oxidative stress defence
and calcium transport control. This review sets out to summarise most recent findings
for the importance of selenium in muscle function and the contribution of this
information to the design of strategies to cure the diseases
Salmonella enterica Serovar Typhimurium Lacking hfq Gene Confers Protective Immunity against Murine Typhoid
Salmonella enterica is an important enteric pathogen and its various serovars are involved in causing both systemic and intestinal diseases in humans and domestic animals. The emergence of multidrug-resistant strains of Salmonella leading to increased morbidity and mortality has further complicated its management. Live attenuated vaccines have been proven superior over killed or subunit vaccines due to their ability to induce protective immunity. Of the various strategies used for the generation of live attenuated vaccine strains, focus has gradually shifted towards manipulation of virulence regulator genes. Hfq is a RNA chaperon which mediates the binding of small RNAs to the mRNA and assists in post-transcriptional gene regulation in bacteria. In this study, we evaluated the efficacy of the Salmonella Typhimurium Δhfq strain as a candidate for live oral vaccine in murine model of typhoid fever. Salmonella hfq deletion mutant is highly attenuated in cell culture and animal model implying a significant role of Hfq in bacterial virulence. Oral immunization with the Salmonella hfq deletion mutant efficiently protects mice against subsequent oral challenge with virulent strain of Salmonella Typhimurium. Moreover, protection was induced upon both multiple as well as single dose of immunizations. The vaccine strain appears to be safe for use in pregnant mice and the protection is mediated by the increase in the number of CD4+ T lymphocytes upon vaccination. The levels of serum IgG and secretory-IgA in intestinal washes specific to lipopolysaccharide and outer membrane protein were significantly increased upon vaccination. Furthermore, hfq deletion mutant showed enhanced antigen presentation by dendritic cells compared to the wild type strain. Taken together, the studies in murine immunization model suggest that the Salmonella hfq deletion mutant can be a novel live oral vaccine candidate
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