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Selected AbstractsForebrain projections to the hypothalamus are topographically organized in anurans: conservative traits as compared with amniotesEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2005Nerea Moreno Abstract The organization of the forebrain in amphibians (anamniotes) is currently being re-evaluated in terms of evolution and several evidences have corroborated numerous traits shared by amphibians and amniotes, such as the organization of the basal ganglia and the amygdaloid complex. In the present study we have analysed the organization of forebrain afferent systems to the hypothalamus of the frog Rana perezi. In vivo and in vitro tract-tracing techniques with dextran amines and immunohistochemistry for localizing nitric oxide synthase (NOS) in a series of single or combined experiments were used as NOS labelling reveals hypothalamic afferents arising from the lateral amygdala and the combination allowed analysis of the relationship between fibers of different origins in the same section. The results showed a large segregation of afferents in the hypothalamic region depending on their site of origin in the forebrain. Four highly topographically organized prosencephalic tracts reaching the anuran hypothalamus were observed: (i) the medial forebrain bundle, from the medial pallium and septal complex; (ii) the caudal branch of the stria terminalis formed by fibers arising in the lateral and medial amygdala; (iii) part of the lateral forebrain bundle with fibers from the central amygdala and (iv) the dorsal thalamo-hypothalamic tract. Fibers coursing in each tract reach the hypothalamus and terminate in distinct fields. The resemblance in pattern of forebrain-hypothalamic organization between amphibians and amniotes suggests that this feature represents an important trait conserved in the evolution of all tetrapods and therefore essential for the hypothalamic function. [source] Effects of sand sedimentation on the macroinvertebrate fauna of lowland streams: are the effects consistent?FRESHWATER BIOLOGY, Issue 1 2006BARBARA J. DOWNES Summary 1. In lowland streams sand sedimentation can produce sand slugs: very slow moving, discrete volumes of sand that are created episodically. Hypothetically, such sedimentation causes losses of habitat and fauna but little is known about the effects of sand slugs. In south-eastern Australia sand slugs are widespread, especially in streams with granitic catchments. 2. This study in north-central Victoria was centred on three streams that rise in the Strathbogie Ranges and flow out onto lowland plains, where they contain sand slugs. Below the sand slugs, the streams are slow-flowing ,chains of ponds' with a clay streambed. To correct for potential upstream-downstream confounding of comparisons, two unsanded, nearby streams were included as potential controls. Habitat measurements and faunal samples were taken in Spring 1998, from three sites in the sand slug and three sites in the clay-bed, downstream sections of each impacted stream, as well as from three sites in commensurate upstream and downstream sections of the control streams. 3. The sand-slugged sections had significantly higher velocities, shallower depths and less coarse woody debris than the unsanded downstream sections. Macroinvertebrate taxon richness and abundance showed some significant differences between the sand and clay sections compared with commensurate up- and downstream locations in the control streams. Effects were not uniform, however. In Castle Creek there were no significant differences between the sand and clay sections, in Pranjip-Ninemile Creek taxon richness and abundances were higher in sand than in the clay sections, whereas in Creightons Creek the ,expected' results of lower taxon richness and abundance in the sand were found. 4. Of the 40 most common taxa, only eight provided a clear signal related to sand and, of these, one (Slavina sp.) occurred only in the sand slugs, whereas the other seven had significantly higher numbers in the clay sections. Of these taxa, three were ostracods, three were chironomids and one was a tubificid oligochaete, all taxa that live in detritus-rich environments. Overall faunal composition did not show a clear distinction though, between sandy and clay sites. The sand slug community of Creightons Creek was very different from the other communities in all of the streams. There were clear differences in community composition between the sand-affected and the control streams, even for downstream, clay sections, suggesting they cannot act as controls for the impacted sections of the sand-slugged streams. 5. Differences between streams within categories (particularly between sand-slugged streams) and between sites in the same section of stream accounted for most of the variability in species richness and the abundances of each of the 40 most common taxa. That finding was repeated when data were examined at the family level, for both numbers of families per sample and collated lists of families occurring across sites. These results strongly suggest that the effects of sedimentation by sand slugs do not overwhelm background variation in macroinvertebrate density and diversity. Overall the results suggest that many taxa may respond individually, and that there is much variation between sand-affected streams even over relatively small (approximately <10 km) spatial scales. [source] A spatially advancing turbulent flow and heat transfer in a curved channelHEAT TRANSFER - ASIAN RESEARCH (FORMERLY HEAT TRANSFER-JAPANESE RESEARCH), Issue 1 2010Koji Matsubara Abstract Direct numerical simulation was performed for a spatially advancing turbulent flow and heat transfer in a two-dimensional curved channel, where one wall was heated to a constant temperature and the other wall was cooled to a different constant temperature. In the simulation, fully developed flow and temperature from the straight-channel driver was passed through the inlet of the curved-channel domain. The frictional Reynolds number was assigned 150, and the Prandtl number was given 0.71. Since the flow field was examined in the previous paper, the thermal features are mainly targeted in this paper. The turbulent heat flux showed trends consistent with a growing process of large-scale vortices. In the curved part, the wall-normal component of the turbulent heat flux was twice as large as the counterpart in the straight part, suggesting active heat transport of large-scale vortices. In the inner side of the same section, temperature fluctuation was abnormally large compared with the modest fluctuation of the wall-normal velocity. This was caused by the combined effect of the large-scale motion of the vortices and the wide variation of the mean temperature; in such a temperature distribution, large-scale ejection of the hot fluid near the outer wall, which is transported into the near inner-wall region, should have a large impact on the thermal boundary layer near the inner wall. Wave number decomposition was conducted for various statistics, which showed that the contribution of the large-scale vortex to the total turbulent heat flux normal to the wall reached roughly 80% inside the channel 135° downstream from the curved-channel inlet. © 2009 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20275 [source] CNN applications from the hardware point of view: video sequence segmentationINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 2-3 2002Asko Kananen Abstract In this paper, the problems present in hardware implementations of cellular non-linear network (CNN) type parallel processors are discussed. Instead of designing a multipurpose processor, or even a full image size application specific parallel processor, we suggest a division of the processing task into categories depending on the cell dynamics and on the spread of the influence of a cell. In this way, drastic savings can be achieved in silicon size and in processing speed. As an example, we use a CNN algorithm that was designed for video image segmentation for object-based compression of video signal. We start with discussion of the problems related to implementation of the algorithm with current multipurpose processors. We then introduce hardware structures that can be used in obtaining certain functionalities. In the same section, we also deal with the division of the processing task. We also compare the introduced hardware solution for the algorithm with multipurpose processor structures in silicon size, power consumption and in processing speed. Copyright © 2002 John Wiley & Sons, Ltd. [source] FGFR3 protein expression and its relationship to mutation status and prognostic variables in bladder cancer,THE JOURNAL OF PATHOLOGY, Issue 1 2007DC Tomlinson Abstract FGFR3 is frequently activated by mutation in urothelial carcinoma (UC) and represents a potential target for therapy. In multiple myeloma, both over-expression and mutation of FGFR3 contribute to tumour development. To define the population of UC patients who may benefit from FGFR-targeted therapy, we assessed both mutation and receptor over-expression in primary UCs from a population of new patients. Manual or laser capture microdissection was used to isolate pure tumour cell populations. Where present, non-invasive and invasive components in the same section were microdissected. A screen of the region of the highest tumour stage in each sample yielded a mutation frequency of 42%. Mutations comprised 61 single and five double mutations, all in hotspot codons previously identified in UC. There was a significant association of mutation with low tumour grade and stage. Subsequently, non-invasive areas from the 43 tumours with both non-invasive and invasive components were analysed separately; 18 of these had mutation in at least one region, including nine with mutation in all regions examined, eight with mutation in only the non-invasive component and one with different mutations in different regions. Of the eight with mutation in only the non-invasive component, six were predicted to represent a single tumour and two showed morphological dissimilarity of fragments within the block, indicating the possible presence of distinct tumour clones. Immunohistochemistry showed over-expression of FGFR3 protein in many tumours compared to normal bladder and ureteric controls. Increased expression was associated with mutation (85% of mutant tumours showed high-level expression). Overall, 42% of tumours with no detectable mutation showed over-expression, including many muscle-invasive tumours. This may represent a non-mutant subset of tumours in which FGFR3 signalling contributes to the transformed phenotype and which may benefit from FGFR-targeted therapies. Copyright © 2007 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. [source] mRNA expression of urokinase and plasminogen activator inhibitor-1 in human crescentic glomerulonephritisHISTOPATHOLOGY, Issue 2 2001H S Lee mRNA expression of urokinase and plasminogen activator inhibitor-1 in human crescentic glomerulonephritis Aims:,Weak staining for urokinase-plasminogen activator (uPA), tissue type plasminogen activator (tPA), or plasminogen activator inhibitor-1 (PAI-1) confined to crescents has been described in a few cases of severe crescentic glomerulonephritis. We evaluated the molecular mechanism by which these proteins are increased or induced within crescents. Methods and results:,We examined uPA, tPA and PAI-1 mRNA expression in 12 renal biopsies with crescentic glomerulonephritis, and in six control renal biopsies with no detectable abnormalities by RNA in-situ hybridization. The expressions of uPA, tPA and PAI-1 proteins were also assessed by immunofluorescence. To better determine the cellular origin of uPA and PAI-1 transcripts, CD68 protein was studied by immunohistochemistry on the same sections on which in-situ hybridization had been performed. In controls, there were very low level signals of uPA and PAI-1 mRNAs in a few glomerular epithelial cells (GECs). Specific signals of uPA and PAI-1 mRNAs were detected in the cells forming crescents in all the cases with crescentic glomerulonephritis. However, weak expression of mRNA for tPA was detected in two cases only. Immunostaining for uPA and PAI-1 was positive in some but not all, cases of crescentic glomerulonephritis. A double-labelling study showed that the signal for PAI-1 and uPA mRNAs was mainly in CD68, cells. Conclusions:,Local accumulation of uPA or PAI-1 in crescents is associated with enhanced mRNA expression of these proteins. The up-regulation of PAI-1 mRNA by GECs, in particular, could play a major role in the formation of persistent fibrin deposits and progression of the lesions in crescents. Whether up-regulation of uPA is an epiphenomenon or plays a pathogenic role in the formation of crescents remains to be clarified. [source] Vascular endothelial growth factor (VEGF), VEGF receptors expression and microvascular density in benign and malignant thyroid diseasesINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2007Ala'eddin Jebreel Summary Angiogenesis is critical for the growth and metastatic spread of tumours. Vascular endothelial growth factor (VEGF) is the most potent inducer of neovasculature, and its increased expression has been related to a worse clinical outcome in many diseases. The purpose of this study was to evaluate the relation between VEGF, its receptors (VEGFR-1 and VEGFR-2) and microvessel density (MVD) in thyroid diseases. Immunostaining for VEGF and VEGF receptors was performed in 66 specimens of thyroid tissue, comprising 17 multinodular goitre (MNG), 14 Graves' disease, 10 follicular adenoma, 8 Hashimoto's thyroiditis, 7 papillary carcinoma and 10 normal thyroid specimens. Thyrocyte positivity for VEGF and VEGF receptors was scored 0,3. Immunohistochemistry for CD31, and CD34 on the same sections was performed to evaluate MVD. Immunohistochemical staining of VEGF in thyrocytes was positive in 92% of all the thyroid tissues studied. Using an immunostaining intensity cut off of 2, increased thyrocyte staining was seen in follicular adenoma specimens, MNG and normal thyroids compared with Hashimoto's thyroiditis and Graves' disease (P < 0.05). Similarly, VEGF thyrocyte expression in Graves' disease was less than other pathologies (P < 0.05). VEGFR-1 expression and the average MVD score did not differ between the different thyroid pathologies. VEGF expression was lower in autoimmune pathologies compared to autonomous growth processes. Conversely, both VEGFR-1 and VEGFR-2 were widely expressed in benign and neoplastic thyroid disease, suggesting that the up-regulation of VEGF and not its receptors occurs as tissue becomes autonomous. There was no clear relationship between MVD measurement and thyroid pathology. [source] Quantification of red myotomal muscle volume and geometry in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis) using T1 -weighted magnetic resonance imagingJOURNAL OF MORPHOLOGY, Issue 4 2007Cameron N. Perry Abstract T1 -weighted magnetic resonance imaging (MRI) in conjunction with image and segmentation analysis (i.e., the process of digitally partitioning tissues based on specified MR image characteristics) was evaluated as a noninvasive alternative for differentiating muscle fiber types and quantifying the amounts of slow, red aerobic muscle in the shortfin mako shark (Isurus oxyrinchus) and the salmon shark (Lamna ditropis). MRI-determinations of red muscle quantity and position made for the mid-body sections of three mako sharks (73.5,110 cm fork length, FL) are in close agreement (within the 95% confidence intervals) with data obtained for the same sections by the conventional dissection method involving serial cross-sectioning and volumetric analyses, and with previously reported findings for this species. The overall distribution of salmon shark red muscle as a function of body fork length was also found to be consistent with previously acquired serial dissection data for this species; however, MR imaging revealed an anterior shift in peak red muscle cross-sectional area corresponding to an increase in body mass. Moreover, MRI facilitated visualization of the intact and anatomically correct relationship of tendon linking the red muscle and the caudal peduncle. This study thus demonstrates that MRI is effective in acquiring high-resolution three-dimensional digital data with high contrast between different fish tissue types. Relative to serial dissection, MRI allows more precise quantification of the position, volume, and other details about the types of muscle within the fish myotome, while conserving specimen structural integrity. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Correlation with digital dermoscopic images can help dermatopathologists to diagnose equivocal skin tumoursBRITISH JOURNAL OF DERMATOLOGY, Issue 3 2006J. Bauer Summary Background, A variety of pigmented skin tumours can lead to diagnostic difficulties in dermatopathology. Objectives, To investigate whether the interobserver agreement between histopathological diagnoses of equivocal pigmented tumours made by two referral centres can be improved by additional use of dermoscopic images. Material and methods, Retrospective study using 160 tumours excised in the pigmented skin lesions clinic in Graz and 141 from Tübingen. Tumours were diagnosed in the referring centres using clinical data, histopathology and, if required, immunohistochemistry. The tumours were initially diagnosed as 74 melanomas, 218 melanocytic naevi and nine nonmelanocytic tumours. Haematoxylin and eosin sections, patients' age and sex, tumour localization and digital dermoscopic images were then exchanged between the participating centres. Then, diagnoses were made initially based solely on dermatopathology and clinical information. After a washout phase, the same sections were reevaluated with the additional use of dermoscopic images. The main outcome measures were the Cohen's , -coefficients of the initial diagnoses of the centre submitting the cases and the diagnoses of the other centre without and with dermoscopy. Results, The , -coefficient between the initial diagnoses with those made by the second centre without dermoscopy was 0·90 in Graz, 0·73 in Tübingen, and 0·81 overall. With the additional use of dermoscopy the , -value was invariably high with 0·89 in Graz, and improved to 0·87 in Tübingen, and to 0·88 overall. Conclusions, The additional use of digital dermoscopic images further improved the overall very good agreement of histopathological diagnoses between two referral centres. [source] | ||||||||||||||||