666 research outputs found
Relationship between serum level of interleukin-2 in patients with systemic lupus erythematosus and disease activity in comparison with control group
Background: Despite the large number of surveys, there are not any validated biomarkers for SLE disease activity till now. This study aimed to evaluate the relationship between serum level of IL-2 in patients with SLE and disease activity in comparison with control group. Materials and Methods: In this case-control study, 73 patients with lupus and 73 healthy subjects referred to the rheumatology clinic of 5 Azar Hospital in Gorgan (North of Iran).They were studied via convenience sampling during 2011-2012. Blood samples were taken from both groups and serum levels of interleukin -2 measured by Avi Bion Human IL-2 ELISA kit. Serum Level of IL-2 greater than 15 pg/ml defined positive and lesser than this amount defined negative. Disease activity evaluated with SLE disease activity index. Score greater than or equal to three or four defined as active disease. Data analysis conducted by SPSS software (version 16) and by using descriptive statistics and statistical tests. Results: Serum level of IL-2 was positive in 45.2% of sample studied and negative in 54.8% in case group, while in control group, serum level of IL-2 only in 11% of sample studied was positive and in 89% was negative. Statistical analysis indicated a significant relationship between serum level of IL-2 and the SLE disease activity index (p=0.025). Conclusion: This study showed the relationship between serum levels of IL-2 and disease activity, so this biomarker can be used as a clinical indicator for assessing disease activity in patients with SLE
A rare presentation of the Klinefelter's syndrome
A 16 years old boy with Chronic Renal Failure (CRF) was not suspected of having Klinefelter's syndrome until he complained of painful gynecomastia. He was under haemodialysis for 2 years. At first, he was in an approximately full pubertal development (P5, G5), but he had a small and a firm testis (length 2.2cm) and some degree of facial male pattern hair. He also had a decreased upper to lower body segment ratio and despite having chronic renal failure, he was taller than his parents and siblings. His laboratory tests showed high levels of FSH and normal levels of LH and testosterone. With regards to all these findings, we suspected that there might be an occult Klinefelter's syndrome. So, we made his karyotype that showed a 47XXY pattern. Because there are only a few number of cases that have occult Klinefelter's syndrome in the basis of chronic renal failure, we decided to report this case
Different features in Wegener's granulomatosis: Report of five cases
Wegener's granulomatosis (WG) is an autoimmune inflammatory condition. It is often a rapidly progressive and potentially fatal disease. The clinical presentation of WG can be so diverse that the list of its differential diagnosis is vast, ranging from infectious diseases to other vasculitis (e.g. Behcet's disease), as well as malignancies. The exact aetiology of WG remains unclear. The upper airway diseases including sinusitis, oral lesions and otitis media are the most common presenting features of WG. In this paper, we have described 5 WG cases. They had different presentations and chief complaints. Some of them presented with upper airways diseases, while the others mainly suffered from the manifestations of pulmonary involvement. Although all of them were finally diagnosed as WG cases, the processes of the work up for the diagnosis as well as the outcome of the disease were not the same. So, the diversities in the presentation should be mentioned in the management of the WG suspected patients
Study of the effect of plant growth regulators, size, and cultivar of the grape inflorescence explant on production of phenolic compounds in an <em>in vitro </em>condition
Introduction: Phenolic compounds are a large number of secondary metabolites that have useful and desirable effects in the field of agriculture, medicine, and food. This research was aimed to achieve methods of in vitro propagation of grapevine in order to apply biotechnologies for correction, growth, and optimization of products and compounds of the cultivated plant in relation to phenol ratio. Methods: In this interventional study, the effects of cultivar and size of the inflorescence explant and the gibberellin hormone in two levels, benzylaminopurine, and auxin hormones in three levels with three replicates per treatment were evaluated in relation to phenol ratio, in order to evaluate the effect of plant growth regulators, the type and size of the grape inflorescence explant on the phenol production. Results: The type of plant growth regulators affected phenolic substances production. The production of phenolic substances decreased in a medium with the highest concentration of growth regulators, 4 and 2.5 μM concentration of benzylaminopurine, and 4.9 μM of auxin. Production of phenolic substances increased in the free-plant hormone medium. In smaller samples tendency to turn brown was more regarding high amount of the sugar. Conclusion: The plant sample and the cultivar as important factors in producing phenol environment are induced by environmental stimuli like sugar, light, temperature, stress, ozone, and wound and can be actually applied to increase phenol production.</p
Dependence of chaotic behavior on optical properties and electrostatic effects in double beam torsional Casimir actuation
We investigate the influence of Casimir and electrostatic torques on double
beam torsional microelectromechanical systems with materials covering a broad
range of conductivities of more than three orders of magnitude. For the
frictionless autonomous systems, bifurcation and phase space analysis shows
that there is a significant difference between stable and unstable operating
regimes for equal and unequal applied voltages on both sides of the double
torsional system giving rise to heteroclinic and homoclinic orbits,
respectively. For equal applied voltages, only the position of a symmetric
unstable saddle equilibrium point is dependent on the material optical
properties and electrostatic effects, while in any other case there are stable
and unstable equilibrium points are dependent on both factors. For the
periodically driven system, a Melnikov function approach is used to show the
presence of chaotic motion rendering predictions of whether stiction or stable
actuation will take place over long times impossible. Chaotic behavior
introduces significant risk for stiction, and it is more prominent to occur for
the more conductive systems that experience stronger Casimir forces and
torques. Indeed, when unequal voltages are applied, the sensitive dependence of
chaotic motion on electrostatics is more pronounced for the highest
conductivity systems.Comment: 24 pages, 11 figure
Kelussia odoratissima Mozaffarian inhibits ileum contractions through voltage dependent and beta adrenergic receptors
The anti-spasm properties of Kelussia odoratissima Mozaffarian have been mentioned in Iranian traditional medicine and it is used to gastrointestinal disorders treatment. The plant leaf alcoholic extract cumulative effect of this plant on Wistar rats ileum contractions and expression of its probable mechanism was investigated in this research. Hydro-alcoholic extract was prepared by maceration method using 70% ethanol. Forty eight male Wistar rats (150-200 g) were randomly designated to 6 random groups with 8 rats in each, in this interventional research as following. Control group, cumulative concentrations of Kelussia odoratissima Mozaffarian extract receiving group, propranolol receiving group, naloxone receiving group, L-NAME receiving group, and sodium chloride receiving group. Ileum samples were taken from rat and subjected to lgr tension in tissue-bath containing tyrode solution. Isotonic contractions was recorded following addition of potassium chloride (60mM), saline or 10% and 20% cumulative concentrations of Kelussia odoratissima Mozaffarian extract. In order to understand the above mechanism, ileum was incubated with L-NAME, naloxone or propranolol and also affected by different doses of calcium chloride. Then, the observed effect was recorded and the variation percentage was calculated. Statistical analysis was performed by parametric test, repeated measures, ANOVA and t test. Findings: 10% and 20% cumulative concentrations from alcoholic extracts of Kelussia odoratissima Mozaffarian could reduce contractions caused by potassium chloride (P0.05). Beta adrenergic receptor blocker (1 mu M propranolol), significantly decreased the contractions caused by potassium chloride (P-value=0.013) but nitric oxide inhibitor (100 mu M L-NAME) and opioid receptor blocker (1 mu M naloxone) had no effect on this contraction. Calcium was also caused tissue contraction depolarized by potassium chloride and this contraction effect reduced by cumulative concentration (P<0.001). In general it can be concluded that Kelussia alcoholic extracts can inhibit ileum contractions of rat through the effect on voltage dependent and beta adrenergic receptors and it might be used to relieve intestinal spasms. Sedighi M, Rafieian-kopaei M and Noori-Ahmadabadi M. Kelussia odoratissima Mozaffarian inhibits ileum contractions through voltage dependent and beta adrenergic receptors. Life Sci J 2012;9(4):1033-1038]. (ISSN: 1097-8135). http://www.lifesciencesite.com. 15
Change in bone mineral density in post menopausal women with rheumatoid arthritis
Introduction: Low bone mass is a serious complication of post menopausal women with rheumatoid arthritis. We determined the Change in Bone Mineral Density in postmenopausal women with rheumatoid arthritis. Methods: This retrospective cohort study was carried out on consecutive postmenopausal women with rheumatoid arthritis who were referred to the Azar 5th teaching hospital affiliated to Golestan University of Medical Sciences, North of Iran in 2009. The required data were gathered from the patients' medical records. The data were analyzed using SPSS software and statistical tests. Results: We studied 98 postmenopausal women with rheumatoid arthritis. Mean number of years since menopause and mean duration of disease were 9.39 and 5.13 respectively. T Score mean in femoral neck and lumbar spines was -1.45±1.26 and -2.45±1.44 respectively. The overall prevalence of osteoporosis at both the lumbar spine and femoral neck was 13.3. We have found a significant correlation between age, duration of disease, duration of menopause and bone mineral density (P-Value<0.01). Conlusion: Our results indicate a negative effect of age, number of years since menopause and duration of disease on bone mineral density. So, BMD should be measured in high risk women prior to the implementation of any treatment or prevention program
Dynamical Casimir actuation under non-equilibrium conditions:The influence of optical properties from different interacting bodies
In this work we investigated the dynamical actuation of microsystems with non-identical material components in the presence of non-equilibrium Casimir forces between Au and highly doped SiC that show significant difference in conductivity. For autonomous systems, the bifurcation and phase space analysis revealed that when the less conductive material operates at higher temperature, then at short separations the non-equilibrium force causes instability. Furthermore, for periodically driven systems the Melnikov function and Poincare portrait analysis showed that the devices are more robust against chaotic motion when the less conductive component is at low temperature at short separations. At larger separations chaotic behavior is more likely to occur for systems with the more conductive component at higher temperature.</p
A survey of Hopf bifurcation analysis in nonlinear railway wheelset dynamics
This article attempts to analyze the Hopf bifurcation behavior of a railway wheelset in the presence of dead-zone and yaw damper nonlinearities. A model that is more precise than Yang and Ahmadian is investigated. Using Bogoliubov-Mitropolsky averaging method and critical speed, the amplitude of the limit cycle in the presence of the mentioned nonlinearities is taken into consideration. To solve these nonlinear equations analytically, the integration interval has been divided into three sub-domains. Two-dimensional bifurcation diagrams are provided to illustrate the mechanism of formation of Hopf bifurcation. These diagrams can be used for design of stable wheelset systems
Sensitivity of actuation dynamics on normal and lateral Casimir forces:Interaction of phase change and topological insulator materials
We investigated here the influence of the lateral and normal Casimir force on the actuation dynamics between sinusoidal corrugated surfaces undergoing both normal and lateral displacements. The calculations were performed for topological insulators and phase change materials that are of high interest for device applications. The results show that the lateral Casimir force becomes stronger by increasing the material conductivity and the corrugations toward similar sizes producing wider normal separation changes during lateral motion. In a conservative system, bifurcation and Poincaré portrait analysis shows that larger but similar in size corrugations and/or higher material conductivity favor stable motion along the lateral direction. However, in the normal direction, the system shows higher sensitivity on the optical properties for similar in size corrugations leading to reduced stable operation for higher material conductivity. Furthermore, in non-conservative systems, the Melnikov function with the Poincaré portrait analysis was combined to probe the possible occurrence of chaotic motion. During lateral actuation, systems with more conductive materials and/or the same but high corrugations exhibit lower possibility for chaotic motion. By contrast, during normal motion, chaotic behavior leading to stiction of the moving components is more likely to occur for systems with more conductive materials and similar in magnitude corrugations
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