Comparative thermal buckling analysis of functionally graded plate

A thermal buckling analysis of functionally graded thick rectangular plates according to von Karman non-linear theory is presented. The material properties of the functionally graded plate, except for the Poisson's ratio, were assumed to be graded in the thickness direction, according to a power-law distribution, in terms of the volume fractions of the metal and ceramic constituents. Formulations of equilibrium and stability equations are derived using the high order shear deformation theory based on different types of shape functions. Analytical method for determination of the critical buckling temperature for uniform increase of temperature, linear and non-linear change of temperature across thickness of a plate is developed. Numerical results were obtained in MATLAB software using combinations of symbolic and numeric values. The paper presents comparative results of critical buckling temperature for different types of shape functions. The accuracy of the formulation presented is verified by comparing to results available from the literature

The significance of Goodpasture antigen in hereditary nephritis

INTRODUCTION: Two types of hereditary nephritis, nonprogressive and progressive, clinically present as asymptomatic haematuria, sometimes combined with proteinuria. At the onset, in both types, light microscopic changes are minimal, immunofluorescence findings are negative, and diagnosis can be made only upon electron microscopic findings that are considered to be specific. OBJECTIVE: The aim of this study was to determine the significance of Goodpasture antigen detection in diagnosis of progressive and nonprogressive hereditary nephritis in its early phase. METHOD: Analysis of renal biopsy specimens was done in patients with hereditary nephritis that were followed from 1990 to 2005. Progression of renal disease was examined in 14 patients with Alport's syndrome, 10 patients with thin basement membrane disease, and 6 patients with unclassified hereditary nephritis diagnosed. For all these cases, indirect immunofluorescence study with serum from a patient with high titer of Goodpasture autoantibodies that recognize the antigenic determinants in human glomerular and tubular basement membrane was performed. RESULTS: In 11 out of 14 cases diagnosed as Alport's syndrome, there was negative staining with Goodpasture serum, and in 3 additional cases with Alport's syndrome, expression of Goodpasture antigen in glomerular basement membrane and thin basement membrane was highly reduced. In all 10 patients with thin basement membrane disease, immunofluorescence showed intensive, bright linear staining with Goodpasture serum along glomerular and tubular basement membrane. In 2 out of 6 patients with unclassified hereditary nephritis, Goodpasture antigen expression was very strong, in one patient it was very reduced, and in 3 patients it was negative. CONCLUSION: The results of our study show that Goodpasture antigen detection plays a very important role in differential diagnosis of progressive and nonpregressive hereditary nephritis, particularly in early phases of the disease

Polycystic kidney disease--autopsy review from the period 1987-2007

INTRODUCTION: Polycystic kidney disease is an inherited kidney disease that affects both kidneys and it is characterized by diffuse replacement of renal parenchyma by thousands of microcysts. In time, renal insufficiency develops. There are two forms of PKD: ADPKD, which is detected in adults (children are rarely affected), and ARPK, which is detected in neonates (later presentations do occur, but rarely). OBJECTIVE: The aim of this study was to analyse frequency of polycystic kidney disease, clinical data and morphological characteristics. METHOD: At the Institute of Pathology, School of Medicine, Belgrade, there were detected 33 cases of ADPKD and 20 cases of ARPKD between 1987 and 2007. RESULTS: There were no differences between incidence of ADPKD in males and females. Average age of patients with ADPKD was 52 years. In 20 (66.7%) cases of ADPKD there were neither extrarenal cysts nor extrarenal manifestations detected. In other 13 cases, we detected extrarenal cysts: hepatic cysts in 8 cases, pancreatic cysts in 5 cases. In two cases, hepatic cysts were associated with intracranial (arachnoid cysts) and extracranial aneurysms. The most frequent cause of death in patients with ADPKD was end-stage disease. ARPKD affects more often male children compared to female. 70% of children with ARPKD were male. The mean age of patients with ARPKD was 1 month. 5 patients (40%) had hepatic fibrosis. The most frequent cause of death was respiratory insufficiency (75%). In 25% of patients, the cause of death was sepsis and renal insufficiency. CONCLUSION: Morphological and clinical manifestations of the analysed cases of both types of PKD are fairly consistent with literature data. Better knowing of aethiopathogenesis of PKD will facilitate early diagnosis, based on clinical and morphological characteristics and better management of the disease

Fullerenol nanoparticles as a new delivery system for doxorubicin

Doxorubicin is a very potent chemotherapeutic drug, however its side effects limit its clinical use. The aim of this research was to investigate the properties of a fullerenol/doxorubicin nanocomposite, its potentially cytotoxic and genotoxic effects on malignant cell lines, as well as its toxicity towards zebra fish embryos. Chromatographic, NMR and mass spectral analysis of the nanocomposite imply that interactions between doxorubicin and fullerenol are non-covalent bonds. The stability of the nanocomposite was confirmed by the use of atomic force microscopy, dynamic light scattering and transmission electron microscopy. The nanocomposite, compared to the free doxorubicin at equivalent concentrations, significantly decreased the viability of MCF-7 and MDA-MB-231 cells. The flow cytometry results indicated that doxorubicin-loaded fullerenol could remarkably increase the uptake of doxorubicin suggesting that fullerenol might be a promising intracellular targeting carrier for the efficient delivery of antitumor drugs into tumor cells. The nanocomposite also affected cell cycle distribution. A genotoxicity test showed that the nanocomposite at all examined concentrations on MCF-7 and at lower concentrations on MDA-MB-231 cells caused DNA damage. Consequently, cell proliferation was notably reduced when compared with controls. Results of the zebrafish embryotoxicity assay showed a decreased overall toxicity, particularly cardiotoxicity and increased safety of the nanocomposite in comparison to doxorubicin alone, as manifested by a higher survival of embryos and less pericardial edema

Цијанобактерије и алге из биофилма са улазне зоне Петничке пећине

The importance of biofilms in caves, the diversity of microorganisms in them, their mutual relationship and relationship with the substratum are among the advancing research topics in microbial biospeleology. This research is making contribution to the knowledge about biofilms at cave entrances and phototrophic communities in them. In that manner, biofilms from the entrance zone of the Petnica Cave were examined. Light microscopy showed that cyanobacteria were exclusively dominant phototrophs (34 taxa out of 39 total taxa recorded) with coccoid forms prevailing (28 taxa); simple trichal forms were present to a lesser extent, while heterocytous ones were completely absent. Genera Gloeocapsa, Chroococcus,Gloeothece and Leptolyngbya were the most diverse. Four green algal genera characteristic for aerophytic habitats (Apatococcus, Desmococcus, Haematococcus and Trentepohlia) were also recorded, while Bacillariophyta were observed sporadically. Three groups of sampling sites were distinguished based on recorded taxa, their richness and similarity, using non-metric multidimensional scaling (NMDS). Quantitative biofilm characteristics were also assessed – the content of chlorophyll a (Chl a) was determined, as well as the contents of water, organic and inorganic matter. Chl a had a significant positive correlation with the content of organic matter (r=0.904, P=0.013).Значај биофилмова у пећинама, разноврсност микроорганизама у њима, њихов међусобни однос, као и однос са супстратом, спадају у водеће теме истраживања у пољу микробијалне биоспелеологије. Ово истраживање доприноси општем познавању биофилмова на улазима пећина, као и познавању фототрофних заједница које се налазе у њиховом саставу. Имајући то у виду, испитивани су биофилмови са улазне зоне Петничке пећине. Светлосна микроскопија је показала да су цијанобактерије искључиво доминантни фототрофи (забележено је 34 од укупно 39 таксона), са изузетном доминацијом кокоидних форми (28 таксона); трихалне форме (хомоцитни представници) су у биофилму заступљене у мањој мери, док су хетероцитне потпуно одсутне. У родовима Gloeocapsa, Chroococcus, Gloeothece и Leptolyngbya документован је највећи број таксона. Четири рода зелених алги која су иначе карактеристична за аерофитска станишта (Apatococcus, Desmococcus, Haematococcus и Trentepohlia) су такође забележена, док су представници раздела Bacillariophyta нађени спорадично. Статистичка анализа NMDS је показала да су се према сличности, односно на основу таксона који су идентификовани, одвојиле три групе тачака узорковања. Kвантитативне карактеристике биофилма су такође процењене – одређен је садржај хлорофила а (Chl a), као и садржај воде, органске и неорганске материје. Значајнa позитивна корелација (r=0.904, P=0.013) уочена је између садржаја органске материје и Chl a

Iga nephropathy: clinical-morphologic correlation

IgA nephropathy is glomerular disease caracterized by the presencemorphologic changes as wella as the prognosis is in correlation with of IgA dominant or codominant imunoglobuline deposits in glomer-the amount of proteinuria. The prognosis is better in children. ular mesangium which can be demostrated by immunofluorescence. Clinical manifestations of IgA nephropathy in the majority of cases is hematuria which can be macro or mikroskopic, isolated or combined with proteinuria, which can be of nephrotic range. The prognosis o the disease is better if presented with haematuria. Intensity of????

Phylogeographic and taxonomic considerations on Goniolimon tataricum (Plumbaginaceae) and its relatives from south-eastern Europe and the Apennine Peninsula

Goniolimon species are mainly components of the Eurasian steppe or steppe-like rocky vegetation, with some taxa occurring also in south-eastern Europe and northern Africa. We analysed the variability of: (i) two maternally inherited plastid loci (rpl32-trnL and 3 ' rps16-5 ' trnK) in 110 individuals of six currently accepted species from the Balkans and one species from the Apennines, to provide new insights into their origin and evolutionary history; and (ii) quantitative morphological characters (14 independent characters and one ratio character) in 641 individuals of three species of which two are morphologically and ecologically similar (G. italicum and G. tataricum) and the third, G. dalmaticum, was frequently misidentified as G. tataricum in the past, to provide new taxonomic treatment for proposed G. tataricum subspecies. We delineated several quantitative and five qualitative characters studied in a more limited sample as diagnostic for the identification of four subspecies (three newly described and one in a new rank) of G. tataricum. The history of westward peripheral populations of this species in the Balkans and the Apennines was rather complex and driven by local geo-historic events. These events facilitated multiple waves of east-west expansion of lineages originating from sources outside of the Balkan Peninsula which periodically diversified and occupied localised areas in the Balkans during the Pleistocene. An initial spread of an ancient G. tataricum lineage throughout south-eastern Europe probably occurred during the Messinian Salinity Crisis. Inter- and intraspecific hybridisation/introgression, as well as retention of ancestral polymorphisms, was common in G. tataricum and related taxa over time

Expression analysis of genes involved in apoptosis, proliferation and endoplasmic reticulum stress in ionomycin/PMA treated Jurkat cells

Purpose: Activation of T cells by direct stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Io) results in numerous downstream signals that activate pathways enabling T cells to proliferate and produce cytokines. Inducible T cell activation is regulated predominantly at the transcriptional level. Therefore, we were interested to analyze the transcriptional activity of the 19 genes involved in the regulation of several important cellular processes. Methods: Quantitative real-time (RT) PCR analysis was performed using mRNA-specific primers and SybrGreen for relative mRNA expression levels of all the examined genes. Results: Our results showed c-kit expression in Jurkat cells, further confirmed by sequencing of c-kit mRNA-specific PCR product. The expected increased expression of interleukin (IL)-2 mRNA, together with moderate Ki-67 upregulation, indicate the proliferation of PMA/Io treated Jurkat cells. Significant upregulation of nuclear factor (NF)-kappa B, JNK and the prosurvival Bcl-2 was followed by activation of only one protein kinase RNA-like endoplasmic reticulum kinase (PERK) out of 3 main endoplasmic reticulum (ER) stress subpathways (ATF6 and spliced XBP were downregulated). NF-kappa B and JNK activation, as well as ERK down regulation were reactive oxygen species (ROS)-independent, shown by the lack of activation of antioxidative enzymes (SOD, NOS, GSTP 1, gGCS and GR). C-kit was downregulated in the absence of exogenous SCF (c-kit ligand). Conclusion: Based on these data it is concluded that the PMA/Io treatment of Jurkat cells induced increased expression of IL-2. followed by upregulation of prosurvival genes belonging to the Bcl-2 family. Neither c-kit nor the antioxidative system were activated, excluding their role in Jurkat T-cell activation in the absence of exogenous c-kit ligand SCF.Ministry of Science, Republic of Serbia [OI 173014]; CNRS, France [451-03-2405/2007-02/12-1

Expression analysis of genes involved in apoptosis, proliferation and endoplasmic reticulum stress in ionomycin/PMA treated Jurkat cells

Purpose: Activation of T cells by direct stimulation with phorbol 12-myristate 13-acetate (PMA) and ionomycin (Io) results in numerous downstream signals that activate pathways enabling T cells to proliferate and produce cytokines. Inducible T cell activation is regulated predominantly at the transcriptional level. Therefore, we were interested to analyze the transcriptional activity of the 19 genes involved in the regulation of several important cellular processes. Methods: Quantitative real-time (RT) PCR analysis was performed using mRNA-specific primers and SybrGreen for relative mRNA expression levels of all the examined genes. Results: Our results showed c-kit expression in Jurkat cells, further confirmed by sequencing of c-kit mRNA-specific PCR product. The expected increased expression of interleukin (IL)-2 mRNA, together with moderate Ki-67 upregulation, indicate the proliferation of PMA/Io treated Jurkat cells. Significant upregulation of nuclear factor (NF)-kappa B, JNK and the prosurvival Bcl-2 was followed by activation of only one protein kinase RNA-like endoplasmic reticulum kinase (PERK) out of 3 main endoplasmic reticulum (ER) stress subpathways (ATF6 and spliced XBP were downregulated). NF-kappa B and JNK activation, as well as ERK down regulation were reactive oxygen species (ROS)-independent, shown by the lack of activation of antioxidative enzymes (SOD, NOS, GSTP 1, gGCS and GR). C-kit was downregulated in the absence of exogenous SCF (c-kit ligand). Conclusion: Based on these data it is concluded that the PMA/Io treatment of Jurkat cells induced increased expression of IL-2. followed by upregulation of prosurvival genes belonging to the Bcl-2 family. Neither c-kit nor the antioxidative system were activated, excluding their role in Jurkat T-cell activation in the absence of exogenous c-kit ligand SCF.Ministry of Science, Republic of Serbia [OI 173014]; CNRS, France [451-03-2405/2007-02/12-1

FAILURE CRITERIA OF FIBRE REINFORCED COMPOSITES IN HOMOGENOUS TEMPERATURE FIELD

The present paper examines the failure criteria of layered composites with orthotropic properties in the homogenous temperature field. The composite has modeled by two mechanically equivalent families of fibres. The paper formulates constitutive equations in terms of intrinsic "preferred" directions, which are defined by the orientation of fibers at any point of the composite. A uniformly heated, thermoelastic solid undergoes distortion as well as volume change because it experiences differential expansions in different directions. This effect is more complicated if, in addition of being anisotropic, the material is inhomogeneous, as in the case with laminated materials. In order to illustrate the influence of temperature on the failure of this group of materials constitutive equations are derived and adopted for use in failure criteria, without the influence of temperatures, and with the influence of increased temperature