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Pattern Characteristic (pattern + characteristic)
Selected AbstractsHyalinizing trabecular tumour of the thyroid,differential expression of distinct miRNAs compared with papillary thyroid carcinomaHISTOPATHOLOGY, Issue 5 2010Sien-Yi Sheu Sheu S-Y, Vogel E, Worm K, Grabellus F, Schwertheim S & Schmid K W (2010) Histopathology56, 632,640 Hyalinizing trabecular tumour of the thyroid,differential expression of distinct miRNAs compared with papillary thyroid carcinoma Aims:, To compare the expression pattern of five microRNAs (miRNAs) (146b, -181b, -21, -221, -222) of papillary thyroid carcinoma (PTC) and hyalinizing trabecular tumour of the thyroid (HTT). Methods and results:, The expression pattern of five miRNAs known to be up-regulated in PTC was retrospectively analysed in 18 HTTs, adjacent normal thyroid tissue, 10 PTCs, 10 follicular adenomas and 10 non-toxic multinodular goitres (MNG) by reverse transcriptase-polymerase chain reaction using the TaqMan miRNA assay. Furthermore, the two common genetic alterations characteristic for PTC, the V600E mutation of the BRAF gene and RET/PTC 1 and 3 rearrangements, were determined in all HTTs. All miRNAs were significantly up-regulated in PTCs, whereas all miRNAs in HTT, normal thyroid tissue, adenomas, and MNGs were down-regulated. Calculating relative changes in gene expression, a 510-fold change of miRNA 146b between PTC and HTT could be observed followed by fold changes between 6.4 and 29 in the remaining miRNAs (P < 0.001). All HTTs lacked BRAF mutations and RET/PTC rearrangements. Conclusions:, Our findings do not support the concept that a high proportion of HTT represents a variant of PTC. It is suggested that HTTs lacking both a miRNA expression pattern characteristic for PTC and RET/PTC rearrangements are re-designated as ,hyalinizing trabecular adenomas'. [source] Nuclear changes in necrotic HL-60 cellsJOURNAL OF CELLULAR BIOCHEMISTRY, Issue S36 2001Roberta Bortul Abstract Cell death in eukaryotes can occur by either apoptosis or necrosis. Apoptosis is characterized by well-defined nuclear changes which are thought to be the consequence of both proteolysis and DNA fragmentation. On the other hand, the nuclear modifications that occur during necrosis are largely less known. Here, we have investigated whether or not nuclear modifications occur during ethanol-induced necrotic cell death of HL-60 cells. By means of immunofluorescence staining, we demonstrate that the patterns given by antibodies directed against some nuclear proteins (lamin B1, NuMA, topoisomerase II,, SC-35, B23/nucleophosmin) changed in necrotic cells. The changes in the spatial distribution of NuMA strongly resembled those described to occur during apoptosis. On the contrary, the fluorescent pattern characteristic for other nuclear proteins (C23/nucleolin, UBF, fibrillarin, RNA polymerase I) did not change during necrosis. By immunoblotting analysis, we observed that some nuclear proteins (SAF-A, SATB1, NuMA) were cleaved during necrosis, and in the case of SATB1, the apoptotic signature fragment of 70 kDa was also present to the same extent in necrotic samples. Caspase inhibitors did not prevent proteolytic cleavage of the aforementioned polypeptides during necrosis, while they were effective if apoptosis was induced. In contrast, lamin B1 and topoisomerase II, were uncleaved in necrotic cells, whereas they were proteolyzed during apoptosis. Transmission electron microscopy analysis revealed that slight morphological changes were present in the nuclear matrix fraction prepared from necrotic cells. However, these modifications (mainly consisting of a rarefaction of the inner fibrogranular network) were not as striking as those we have previously described in apoptotic HL-60 cells. Taken together, our results indicate that during necrosis marked biochemical and morphological changes do occur at the nuclear level. These alterations are quite distinct from those known to take place during apoptosis. Our results identify additional biochemical and morphological criteria that could be used to discriminate between the two types of cell death. J. Cell. Biochem. Suppl. 36: 19,31, 2001. © 2001 Wiley-Liss, Inc. [source] Electrophoretic analysis of urinary proteins in diabetic adolescentsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 4 2001George Koliakos Abstract Pathological changes in the urine sodium dodecyl sulphate gel electrophoresis (SDS PAGE) patterns often precede the occurrence of any sign of renal involvement in diabetes. However, data concerning the most frequent SDS PAGE pattern of the urine in early stages of type I diabetes mellitus are controversial. In the present study an SDS PAGE technique has been used that provides an adequate sensitivity for the detection of the abnormal pattern. Urinary proteins have been analyzed by SDS PAGE in twenty two diabetic adolescents and twenty four age matched controls. Albumin concentration, and N acetyl-beta-D-glucosaminidase (NAG) activity were also measured in the same samples. There was no significant difference in urine albumin concentration and NAG activity between diabetic children and controls. However twelve patients showed an electrophoretic pattern characteristic for glomerulopathy, two had a pattern indicating tubular dysfunction and another two patients had a mixed pattern. Among the twenty four controls only three showed abnormal electrophoretic patterns. The results support the view that early stages of diabetic nephropathy may involve both glomerular and tubular dysfunction. However the exact clinical and prognostic significance of the information provided by SDS PAGE analysis remains to be elucidated. J. Clin. Lab. Anal. 15:178,183, 2001. © 2001 Wiley-Liss, Inc. [source] The effect of water to ethanol feed ratio on physical properties and aerosolization behavior of spray dried cromolyn sodium particlesJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 5 2005Kambiz Gilani Abstract Cromolyn sodium (CS) was spray dried under constant operation conditions from different water to ethanol feed ratios (50:50,0:100). The spray dried CS samples were characterized for their physicochemical properties including crystallinity, particle size distribution, morphology, density, and water/ethanol content. To determine quantitatively the crystallinity of the powders, an X-ray diffraction (XRD) method was developed using samples with different crystallinity prepared by physical mixing of 100% amorphous and 100% crystalline CS materials. The aerodynamic behavior of the CS samples was determined using an Andersen Cascade Impactor (ACI) with a Spinhaler® at an air flow of 60 L/min. Binary mixtures of each spray dried CS powder and Pharmatose® 325, a commercial ,-lactose monohydrate available for DPI formulations, were prepared and in vitro aerosol deposition of the drug from the mixtures was analyzed using ACI to evaluate the effect of carrier on deposition profiles of the spray dried samples. CS spray dried from absolute ethanol exhibited XRD pattern characteristic for crystalline materials and different from patterns of the other samples. The crystallinity of spray dried CS obtained in the presence of water varied from 0% to 28.37%, depending on the ratio of water to ethanol in the feed suspensions. All samples presented different particle size, water/ethanol content, and bulk density values. CS particles spray dried from absolute ethanol presented uniform elongated shape whereas the other samples consisted mainly of particles with irregular shape. Overall, fine particle fraction increased significantly (p,<,0.01) with decreasing d50% and water and ethanol content of spray dried CS samples. Significant difference (p,<,0.01) in deposition profiles of the drug were observed between corresponding carrier free and carrier blended formulations. The difference in deposition profiles of CS aerosolized from various spray dried samples were described according to the particle size, shape, and water/ethanol contents of the powders. The results of this study indicate that enhanced aerosol performance of CS can be obtained by spray drying of the drug from suspensions containing ,87.5% v/v ethanol. © 2005 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 94:1048,1059, 2005 [source] Overcoming the restriction barrier to plasmid transformation of Helicobacter pyloriMOLECULAR MICROBIOLOGY, Issue 5 2000John P. Donahue Helicobacter pylori strains demonstrate substantial variability in the efficiency of transformation by plasmids from Escherichia coli, and many strains are completely resistant to transformation. Among the barriers to transformation are numerous strain-specific restriction-modification systems in H. pylori. We have developed a method to protect plasmid DNA from restriction by in vitro site-specific methylation using cell-free extracts of H. pylori before transformation. In two cases, plasmid DNA treated with cell-free extracts in vitro acquired the restriction pattern characteristic of genomic DNA from the source strain. Among three strains examined in detail, the transformation frequency by treated plasmid shuttle and suicide vectors was significantly increased compared with mock-treated plasmid DNA. The results indicate that the restriction barrier in H. pylori can be largely overcome by specific DNA methylation in vitro. The approach described should significantly enhance the ability to manipulate gene function in H. pylori and other organisms that have substantial restriction barriers to transformation. [source] MicroRNA-140 is expressed in differentiated human articular chondrocytes and modulates interleukin-1 responsesARTHRITIS & RHEUMATISM, Issue 9 2009Shigeru Miyaki Objective MicroRNA (miRNA) are a class of noncoding small RNAs that act as negative regulators of gene expression. MiRNA exhibit tissue-specific expression patterns, and changes in their expression may contribute to pathogenesis. The objectives of this study were to identify miRNA expressed in articular chondrocytes, to determine changes in osteoarthritic (OA) cartilage, and to address the function of miRNA-140 (miR-140). Methods To identify miRNA specifically expressed in chondrocytes, we performed gene expression profiling using miRNA microarrays and quantitative polymerase chain reaction with human articular chondrocytes compared with human mesenchymal stem cells (MSCs). The expression pattern of miR-140 was monitored during chondrogenic differentiation of human MSCs in pellet cultures and in human articular cartilage from normal and OA knee joints. We tested the effects of interleukin-1, (IL-1,) on miR-140 expression. Double-stranded miR-140 (ds,miR-140) was transfected into chondrocytes to analyze changes in the expression of genes associated with OA. Results Microarray analysis showed that miR-140 had the largest difference in expression between chondrocytes and MSCs. During chondrogenesis, miR-140 expression in MSC cultures increased in parallel with the expression of SOX9 and COL2A1. Normal human articular cartilage expressed miR-140, and this expression was significantly reduced in OA tissue. In vitro treatment of chondrocytes with IL-1, suppressed miR-140 expression. Transfection of chondrocytes with ds,miR-140 down-regulated IL-1,,induced ADAMTS5 expression and rescued the IL-1,,dependent repression of AGGRECAN gene expression. Conclusion This study shows that miR-140 has a chondrocyte differentiation,related expression pattern. The reduction in miR-140 expression in OA cartilage and in response to IL-1, may contribute to the abnormal gene expression pattern characteristic of OA. [source] Topical paricalcitol (19-nor-1,,25-dihydroxyvitamin D2) is a novel, safe and effective treatment for plaque psoriasis: a pilot studyBRITISH JOURNAL OF DERMATOLOGY, Issue 1 2004C. Durakovic Summary Background, There continues to be a need to develop new pharmacological approaches for treating psoriasis. Topical active vitamin D compounds have proven to be both safe and effective for treating psoriasis. Paricalcitol (19-nor-1,,25-dihydroxyvitamin D2) is a novel vitamin D analogue which has been developed for the prevention of secondary hyperparathyroidism in patients with chronic renal failure. Objectives, To investigate the efficacy and safety of 12 weeks' therapy with a once-daily application of paricalcitol ointment (15 ,g g,1) in comparison with placebo ointment. Methods, This pilot double-blinded self-controlled study was initiated in 11 patients with moderate plaque psoriasis. To characterize the biological effects further and to evaluate the efficacy of topical paricalcitol treatment in psoriasis, we have analysed immunohistochemically the expression of one of the markers for epidermal differentiation (transglutaminase K) in paricalcitol-treated skin as compared with placebo treatment. Results, Treatment with paricalcitol was superior to placebo treatment beginning at week 1. The global severity score for erythema, plaque elevation and scaling was improved significantly more by paricalcitol ointment than by placebo (P < 0·001). Similar results were obtained for assessments of scaling, erythema and plaque elevation. No symptoms of local skin irritation were noted. Laboratory parameters including serum calcium, phosphorus, parathyroid hormone and urinary calcium/creatinine ratio did not reveal any changes of clinical relevance during treatment. The immunoreactivity of transglutaminase K changed after 12 weeks of paricalcitol treatment almost completely to the pattern characteristic for nonlesional psoriatic skin. Conclusions, Once-daily application of paricalcitol ointment was safe and effective for the treatment of plaque psoriasis. [source] Evidence for sexual dichromatisms in spawning aggregations of yellowfin grouper Mycteroperca venenosa and tiger grouper Mycteroperca tigris from the southern Gulf of MexicoJOURNAL OF FISH BIOLOGY, Issue 6 2006A. Tuz-Sulub Colour pattern characteristics and gonad histology were used to detect sexual dichromatisms in yellowfin grouper Mycteroperca venenosa and tiger grouper Mycteroperca tigris from the Campeche Bank, Mexico. Specimens were obtained from commercial catches between March and May during 2002 and 2004. All specimens were examined dead. Ninety-seven per cent of males had different sex-associated colour patterns. Male yellowfin grouper displayed a bright yellow blotch on both sides of the lower jaw while females retained a reddish lower jaw. Male tiger grouper had uniform dark pectoral fins while females had bright orange pectoral fins. In situ observations of live fishes at fishing sites showed the lower jaw and pectoral fin colourations to be clearly visible underwater at a depth of 35 m. All males of both species and most females (80% yellowfin grouper and 98% tiger grouper) were sexually active and probably caught during their spawning season. This suggests that distinct colourations observed for male M. venenosa and M. tigris may be seasonal displays associated with spawning. Both the lower jaw and pectoral fin colourations were still visible in dead fishes after several days on ice. Differences observed for ray length of exserted vertical fins in tiger grouper specimens were probably not a sex-associated characteristic. [source] Comparison of Ricketts analysis and Downs-Northwestern analysis for the evaluation of obstructive sleep apnea cephalogramsPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 3 2001Naoki Higurashi DDS Abstract To determine which analysis is suitable to examine the dentofacial skeletal pattern characteristics of the obstructive sleep apnea syndrome (OSAS), we took lateral cephalograms of 44 Japanese OSAS patients and 34 Japanese non-OSAS controls. By Ricketts analysis, we found significant differences between OSAS patients and non-OSAS controls on facial axis, lower facial height and total facial height, which showed that Japanese OSAS patients have dolico facial patterns. However, by Downs-Northwestern analysis, we did not find any significant difference between OSAS patients and non-OSAS controls using the same cephalograms as the Ricketts analysis. [source] The wealth of species: ecological communities, complex systems and the legacy of Frank PrestonECOLOGY LETTERS, Issue 3 2007Jeffrey C. Nekola Abstract General statistical patterns in community ecology have attracted considerable recent debate. Difficulties in discriminating among mathematical models and the ecological mechanisms underlying them are likely related to a phenomenon first described by Frank Preston. He noted that the frequency distribution of abundances among species was uncannily similar to the Boltzmann distribution of kinetic energies among gas molecules and the Pareto distribution of incomes among wage earners. We provide additional examples to show that four different ,distributions of wealth' (species abundance distributions, species,area and species,time relations, and distance decay of compositional similarity) are not unique to ecology, but have analogues in other physical, geological, economic and cultural systems. Because these appear to be general statistical patterns characteristic of many complex dynamical systems they are likely not generated by uniquely ecological mechanistic processes. [source] Maurice Ravel and right-hemisphere musical creativity: influence of disease on his last musical works?EUROPEAN JOURNAL OF NEUROLOGY, Issue 1 2002L. Amaducci The problem of finding correspondence between a particular neuronal organization and a specific function of the human brain remains a central question of neuroscience. It is sometimes thought that language and music are two sides of the same intellectual coin, but research on brain-damaged patients has shown that the loss of verbal functions (aphasia) is not necessarily accompanied by a loss of musical abilities (amusia). Amusia without aphasia has also been described. This double dissociation indicates functional autonomy in these mental processes. Yet verbal and musical impairments often occur together. The global picture that emerges from studies of music and its neural substrate is by no means clear and much depends on which subjects and which aspect of musical abilities are investigated. An illustration of these concepts is provided by the case of the French composer Maurice Ravel, who suffered from a progressive cerebral disease of uncertain aetiology, with prominent involvement of the left hemisphere. As a result, Ravel experienced aphasia and apraxia and became unable to compose. The available facts favour a clinical diagnosis of primary progressive aphasia (PPA), with the possibility of an overlap with corticobasal degeneration (CBD). In view of Ravel's clinical history, we propose that two of his final compositions, the Bolero and the Concerto for the Left Hand, include certain patterns characteristic of right-hemisphere musical abilities and may show the influence of disease on the creative process. [source] Variations in body melanization impact desiccation resistance in Drosophila immigrans from Western HimalayasJOURNAL OF ZOOLOGY, Issue 2 2008R. Parkash Abstract Ectothermic species face problems of water balance under colder and drier climatic conditions in montane localities. We investigated five ecophysiological traits (body melanization, desiccation resistance, rate of water loss or gain and body size) in eight populations of Drosophila immigrans from an altitudinal gradient (600,2226 m) in the Western Himalayas. The traits showed bell-shaped variability patterns characteristic of quantitative traits. For body melanization, we observed high heritability (0.65) on the basis of parent,offspring regression. A comparison of highland versus foothill populations showed significant divergence for all the traits except body size. Darker flies from the highlands exhibited higher desiccation resistance but reduced rate of water loss or gain as compared with lighter flies from the foothills, which showed lower desiccation resistance and higher rates of water loss as well as gain. Lack of differences in the amount of epicuticular lipids cannot account for differential reduction in cuticular water loss in altitudinal populations. However, within- as well as between-population differences in body melanization can account for changes in desiccation resistance and reduction in cuticular water loss. Analyses of highland versus lowland populations as well as in assorted darker and lighter flies from a highland population have shown differences in haemolymph and dehydration tolerance. For the mechanistic basis of desiccation resistance, our results on wild populations of Drosophila immigrans are not in agreement with those reported for laboratory-selected desiccation-resistant strains in Drosophila melanogaster. Thus, ecophysiological mechanisms could be different under laboratory versus field selection. [source] Proteomic analysis of membrane rafts of melanoma cells identifies protein patterns characteristic of the tumor progression stagePROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 22 2008Frédérique Baruthio Abstract The molecular mechanisms controlling the progression of melanoma from a localized tumor to an invasive and metastatic disease are poorly understood. In the attempt to start defining a functional protein profile of melanoma progression, we have analyzed by LC-MS/MS the proteins associated with detergent resistant membranes (DRMs), which are enriched in cholesterol/sphingolipids-containing membrane rafts, of melanoma cell lines derived from tumors at different stages of progression. Since membrane rafts are involved in several biological processes, including signal transduction and protein trafficking, we hypothesized that the association of proteins with rafts can be regulated during melanoma development and affect protein function and disease progression. We have identified a total of 177 proteins in the DRMs of the cell lines examined. Among these, we have found groups of proteins preferentially associated with DRMs of either less malignant radial growth phase/vertical growth phase (VGP) cells, or aggressive VGP and metastatic cells suggesting that melanoma cells with different degrees of malignancy have different DRM profiles. Moreover, some proteins were found in DRMs of only some cell lines despite being expressed at similar levels in all the cell lines examined, suggesting the existence of mechanisms controlling their association with DRMs. We expect that understanding the mechanisms regulating DRM targeting and the activity of the proteins differentially associated with DRMs in relation to cell malignancy will help identify new molecular determinants of melanoma progression. [source] Optimization of quartz tube pyrolysis atmospheric pressure ionization mass spectrometry for the generation of bacterial biomarkersRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 18 2001Ashish Tripathi Experimental procedures were investigated to improve the efflux of biomolecule pyrolyzates from quartz tube pyrolysis under atmospheric pressure ionization mass spectrometry conditions. Heating regimes, airflows, and ion focusing parameters were optimized to increase the informative mass spectral signals generated from the pyrolysis of Gram-positive bacterial spores and vegetative cells. Dipicolinic acid (DPA) is found in 5,15% by weight in Gram-positive Bacillus spores, and the parameter optimization procedures provided an intense mass spectral signature of the m/z 168 protonated DPA molecule with a minimization of pyrolytic and ionization fragments. Moreover, mass spectral information from the optimization protocols yielded peaks and mass patterns characteristic of DNA and RNA nitrogen bases, protein diketopiperazines, and amino sugars. Copyright © 2001 John Wiley & Sons, Ltd. [source] Tropical Pacific Ocean model error covariances from Monte Carlo simulationsTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 613 2005O. Alves Abstract As a first step towards the development of an Ensemble Kalman Filter (EnKF) for ocean data assimilation in the tropical oceans, this article investigates a novel technique for explicitly perturbing the model error in Monte Carlo simulations. The perturbation technique involves perturbing the surface zonal stress. Estimates of the characteristics of the wind stress errors were obtained from the difference between zonal wind fields from the NCEP and ECMWF re-analyses. In order to create random zonal wind stress perturbations, an EOF analysis was performed on the intraseasonally time-filtered difference between the two re-analysis products. The first 50 EOFs were retained and random wind stress fields for each ensemble member were created by combining random amounts of each EOF. Ensemble runs were performed using a shallow-water model, with both short forecasts and long simulations. Results show covariance patterns characteristic of Kelvin wave and Rossby wave dynamics. There are interesting differences between covariances using short forecasts and those using long simulations. The use of the long simulations produced non-local covariances (e.g. negative covariances between east and west Pacific), whereas short forecasts produced covariances that were localized by the time it takes Kevin and Rossby waves to travel over the forecast period and the scales of spatial covariance in the wind stress errors. The ensembles of short forecasts produced covariances and cross-covariances that can be explained by the dynamics of equatorial Rossby and Kevin waves forced by wind stress errors. The results suggest that the ensemble generation technique to explicitly represent the model error term can be used in an EnKF. Copyright © 2005 Royal Meteorological Society [source] | |||||||||||||||||||