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Peripheral Zone (peripheral + zone)
Selected AbstractsPro-apoptotic protein glyceraldehyde-3-phosphate dehydrogenase promotes the formation of Lewy body-like inclusionsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2005Katsumi Tsuchiya Abstract Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) has long been recognized as a classical glycolytic protein; however, previous studies by our group and others have demonstrated that GAPDH is a general mediator initiating one or more apoptotic cascades. Our most recent findings have elucidated that an expression of a pro-apoptotic protein GAPDH is critically regulated at the promoter region of the gene. Apoptotic signals for its subsequent aggregate formation and nuclear translocation are controlled by the respective functional domains harboured within its cDNA component. In this study, coexpression of GAPDH with either wild-type or mutant (A53T) ,-synuclein and less likely with ,-synuclein in transfected COS-7 cells was found to induce Lewy body-like cytoplasmic inclusions. Unlike its full-length construct, the deleted mutant GAPDH construct (C66) abolished these apoptotic signals, disfavouring the formation of inclusions. The generated inclusions were ubiquitin- and thioflavin S-positive appearing fibrils. Furthermore, GAPDH coimmunoprecipitated with wild-type ,-synuclein in this paradigm. Importantly, immunohistochemical examinations of post mortem materials from patients with sporadic Parkinson's disease revealed the colocalized profiles immunoreactive against these two proteins in the peripheral zone of Lewy bodies from the affected brain regions (i.e. locus coeruleus). Moreover, a quantitative assessment showed that about 20% of Lewy bodies displayed both antigenicities. These results suggest that pro-apoptotic protein GAPDH may be involved in the Lewy body formation in vivo, probably associated with the apoptotic death pathway. [source] Reversible protein kinase C activation in PC12 cells: effect of NGF treatmentEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2000Jean-Luc Dupont Abstract Although protein kinase C (PKC) is a key enzyme in the signal transduction process, there is little information on the mechanism leading to PKC activation in living cells. Using a new fluorescence imaging method, we studied this mechanism and correlated PKC conformational changes with intracellular Ca2+ concentration. PC12 cells were simultaneously loaded with Fura-2-AM and Fim-1, two fluorescent probes, which recognize Ca2+ and PKC, respectively. KCl and carbachol (an agonist to muscarinic receptors) applications induced dose-dependent increases of fluorescence for both probes. Both Ca2+ and PKC responses were observed within seconds following KCl or carbachol application, and were reversible upon stimulus withdrawal. PKC activation kinetics was slightly more rapid than the Ca2+ response after KCl application. After nerve growth factor (NGF) treatment of the cells, the amplitude of the KCl-induced PKC responses was larger indicating an increase in the activated PKC-pool in these cells. This difference between control and NGF-treated cells was not observed following carbachol application, suggesting the involvement of different PKC pools. While the Ca2+ response uniformly occurred in the cytosol, the PKC response displayed a patch pattern with higher intensities in the peripheral zone near the plasma membrane. This heterogeneous distribution of PKC activation sites was similar to the immunocytological localization of Ca2+ -dependent and independent PKC isoforms, which suggested that at least several PKC isoforms interacted with intracellular elements. Upon repeated stimulation, the PKC response rapidly desensitized. [source] Peripheral ameloblastoma of the gingiva: the importance of diagnosisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 1 2005Pía López-Jornet Abstract Background: Peripheral ameloblastoma is an extremely rare epithelial odontogenic tumor, limited to the soft tissues of the gums or oral mucosa. Although the lesion is benign, it may be locally aggressive. Methods: The present study describes the case of a 31-year-old male presenting a firm, symptomless tumor mass of irregular appearance and measuring approximately 12 mm in diameter, located in the distal zone of 4.7. Results: An excision biopsy was performed. The lesion was covered with hyperplastic squamous epithelium, with islets of epithelial cells located at subepithelial level. The cells in the peripheral zone adopted a palisade distribution, and presented the appearance of a lax reticulum at central level. A fibroblastic stroma was observed between the islets. The diagnosis was peripheral ameloblastoma. Conclusions: Although the origin of the lesion remains unclear, it is able to recur and undergo malignant transformation. Consequently, peripheral ameloblastoma should not be viewed as a harmless mass. [source] Prostate cancer detection with multi-parametric MRI: Logistic regression analysis of quantitative T2, diffusion-weighted imaging, and dynamic contrast-enhanced MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2009Deanna L. Langer MSc Abstract Purpose To develop a multi-parametric model suitable for prospectively identifying prostate cancer in peripheral zone (PZ) using magnetic resonance imaging (MRI). Materials and Methods Twenty-five radical prostatectomy patients (median age, 63 years; range, 44,72 years) had T2-weighted, diffusion-weighted imaging (DWI), T2-mapping, and dynamic contrast-enhanced (DCE) MRI at 1.5 Tesla (T) with endorectal coil to yield parameters apparent diffusion coefficient (ADC), T2, volume transfer constant (Ktrans) and extravascular extracellular volume fraction (ve). Whole-mount histology was generated from surgical specimens and PZ tumors delineated. Thirty-eight tumor outlines, one per tumor, and pathologically normal PZ regions were transferred to MR images. Receiver operating characteristic (ROC) curves were generated using all identified normal and tumor voxels. Step-wise logistic-regression modeling was performed, testing changes in deviance for significance. Areas under the ROC curves (Az) were used to evaluate and compare performance. Results The best-performing single-parameter was ADC (mean Az [95% confidence interval]: Az,ADC: 0.689 [0.675, 0.702]; Az,T2: 0.673 [0.659, 0.687]; Az,Ktrans: 0.592 [0.578, 0.606]; Az,ve: 0.543 [0.528, 0.557]). The optimal multi-parametric model, LR-3p, consisted of combining ADC, T2 and Ktrans. Mean Az,LR-3p was 0.706 [0.692, 0.719], which was significantly higher than Az,T2, Az,Ktrans, and Az,ve (P < 0.002). Az,LR-3p tended to be greater than Az,ADC, however, this result was not statistically significant (P = 0.090). Conclusion Using logistic regression, an objective model capable of mapping PZ tumor with reasonable performance can be constructed. J. Magn. Reson. Imaging 2009;30:327,334. © 2009 Wiley-Liss, Inc. [source] Pathology of lumbar nerve root compression Part 1: Intraradicular inflammatory changes induced by mechanical compressionJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 1 2004Shigeru Kobayashi Study design: This study is to investigate the intraradicular inflammation induced by mechanical compression using in vivo model. Objectives: The relationship between the intraradicular edema and nerve fiber degeneration induced by mechanical compression was determined in the nerve root. Summary of background data: Recently some studies reported that mechanical compression increased microvascular permeability of the endoneurial capillaries and resulted in an intraradicular inflammation. These changes may be an important factor of the pathogenesis of radiculopathy. However, the natural courses of the intraradicular inflammation after mechanical compression are still poorly understood. Methods: In dogs, laminectomy was performed at L7 and the seventh nerve root was exposed to compression at 7.5 gram force (gf) clipping power. The animals were evaluated at 1 and 3 weeks after clipping. After the appropriate period of nerve root compression, Evans blue albumin (EBA) was injected intravenously. The nerve root sections were divided into two groups. The sections were used to investigate the status of the blood,nerve barrier function under the fluorescence microscope. The other sections were used for light and transmission electron microscopic study. Results: After 1 and 3 weeks, intraradicular edema was observed not only at the site of compression but also in the peripheral zone of a compressed anterior root and in the central zone of a compressed posterior root. The evidence of active Wallerian degeneration was also seen in the area of intraradicular edema. In addition, the nerve roots showing Wallerian degeneration were infiltrated by inflammatory cells, such as macrophages and mast cells. Conclusions: Inflammatory reaction, such as Wallerian degeneration, breakdown of blood,nerve barrier and appearance of macrophage, may be deeply involved in radiculitis arising from mechanical compression, and these factors seem to be important in the manifestation of radiculopathy. © 2003 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved. [source] Angiogenesis and Interstitial Pressure in a Rat Tumour ModelANATOMIA, HISTOLOGIA, EMBRYOLOGIA, Issue 2005H. Hünigen Introduction and Aim:, Angiogenesis, the formation of new blood vessels, is a crucial process in physiological and pathological growth. Pathological angiogenesis is responsible for growth and metastasis of solid tumours, and, when blocked, improves prognosis. As a result of the angiogenic cascade in solid tumours an irregular, leaky capillary network develops. The aim of the present study was to define malignant tumours' vascular characteristics and reveal functional anatomy by quantification of the microvasculature and interstitial pressure (IP) in relation to tumour fluid dynamics as visualized by contrast enhanced magnetic resonance imaging (MRI). Material and Methods:, Dynamic MRI and measurement of the IP was performed in 21 rats implanted with colon carcinomas subcutaneously. Angiogenesis was studied by morphometry of the capillaries, and immunolocalization of the angiogenic factor VEGF and VEGF-Receptor 2. Results and Conclusions:, Histology, immunohistochemistry and MRI confirmed concentric arrangement of 4 tumour zones. The tumour margin included loose connective tissue with abundant mononuclear cells. Many large microvessels were seen in this most intensely vascularized zone. IP measurement in this zone was adjusted to the zero level. Diameter of the peripheral zone of vital cells measured 1.3 mm. Capillaries were smaller and sparse. Dynamic MRI revealed peripheral washout of the contrast agent in this zone. After an initial increase of the signal intensity a hypo-intense rim was formed within a few minutes. The intermediate region was characterized by islands of vital tumour cells containing 3% capillaries (hot spots). The innermost area, the necrotic zone, took 35% of the total tumour area with less than 0.5% vessels. The IP increased from the periphery to the centre. VEGF and VEGF-receptor 2 was found in the vessels of the tumour margin and vital tumour cells of the peripheral zone. From this can be concluded that the peripheral washout phenomenon seems to be correlated with elevated interstitial pressure and increased capillary density and therefore may be a reliable sign of malignancy. [source] Characterization of the anatomical extension pattern of localized prostate cancer arising in the peripheral zoneBJU INTERNATIONAL, Issue 11 2010Mototsugu Muramaki Study Type , Diagnostic (non-consecutive series) Level of Evidence 3b OBJECTIVES To characterize the anatomical extension pattern of prostate cancer arising in the peripheral zone (PZ) in radical prostatectomy (RP) specimens and to evaluate its prognostic significance. PATIENTS AND METHODS Of 174 consecutive patients undergoing RP, 128 diagnosed as having PZ cancer (PZC) were enrolled. The maximum tumour area (MTA) and maximum tumour volume (MTV) in RP specimens were measured using digital planimetry. A circle with an area equal to the MTA, in which the central point was the intersection of the longest line of the MTA and the line perpendicularly bisecting the first line, was defined as a hypothetical extension area, regardless of anatomical structure. The area within this circle that did not overlap the MTA was defined as ,TA. RESULTS There was a significant correlation between the MTV and ,TA/MTA, introduced as a variable representing the degree of PZC extension along the anatomical shape of the PZ. The ,TA/MTA in patients with a MTV of >5 mL was significantly greater than that in those with a MTV of ,5 mL. Furthermore, ,TA/MTA was significantly associated with several prognostic indicators, including extracapsular extension, surgical margin status and perineural invasion. Multivariate analysis identified ,TA/MTA in addition to preoperative serum prostate-specific antigen level, extracapsular extension and surgical margin status as independent predictors of biochemical recurrence after RP. CONCLUSIONS PZC tends to extend along the anatomical shape of the PZ during progression, resulting in higher ,TA/MTA value in advanced PZC than that in early PZC. [source] Gene expression profiling of the human prostate zonesBJU INTERNATIONAL, Issue 4 2006Leonie Van Der Heul-Nieuwenhuijsen OBJECTIVE To investigate differences in gene expression in different zones of the prostate by microarray analyses, to better understand why aggressive tumours predominantly occur in the peripheral zone (PZ), whereas benign prostatic hyperplasia (BPH) occurs almost exclusively in the transition zone (TZ). MATERIALS AND METHODS Expression profiling of both prostate zones was done by microarray analysis. Reverse transcription-polymerase chain reaction (RT-PCR) of the top 18 genes confirmed the microarray analyses. RT-PCR with common cell-type markers indicated that the differential expression between the zones was not caused by an unequal distribution of different cell types. Primary stromal and epithelial prostate cells were used to study cell type expression in the 12 highest differentially expressed zonal-specific genes. RESULTS In all, 346 genes were identified as preferentially expressed in the TZ or PZ. A few of the TZ-specific genes, including ASPA, FLJ10970 and COCH, were also stroma-specific. Comparisons with other microarray studies showed that gene expression profiles of prostate cancer and BPH correlate with the expression profiles of the PZ and TZ, respectively. CONCLUSION Gene expression differs between the PZ and TZ of the prostate, and stromal,epithelial interactions might be responsible for the distinct zonal localization of prostate diseases. [source] Changing the economic landscape: The phenomenon of regional inversion in the US manufacturing sector,PAPERS IN REGIONAL SCIENCE, Issue 4 2002Luis Fernando Lanaspa-Santolaria Regional Inversion; US manufacturing sector; unit root tests; structural breaks Abstract Regional inversion is the name given to the phenomenon whereby the traditional industrial areas of certain countries lose their weight in favor of what were formerly peripheral zones. Against this background our first objective is to offer a formal and rigorous definition of the concept of regional inversion from an econometric standpoint. To that end we relate such a process with the long-run concepts of convergence and catching-up. Secondly, we test this definition through the use of unit root statistics and apply these to demonstrate the presence of this phenomenon in some of the US two-digit SIC industries. [source] | |||||||||||||