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Stained Sections (stained + section)
Selected AbstractsBacterial invasion of dentinal tubules beneath apparently intact but hypomineralized enamel in molar teeth with molar incisor hypomineralizationINTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 5 2008TOBIAS G. FAGRELL Background., The most common problems for a patient with molar incisor hypomineralization (MIH) are the collapse of enamel and cavitations, loss of fillings, and secondary caries, but most of all, severe hypersensitivity. Objective., The aim of this paper was therefore to histologically study possible bacterial invasion of dentinal tubules beneath apparently intact, but hypomineralized enamel in permanent molars with MIH. Material and methods., Five extracted permanent first molars diagnosed with MIH were fixated, demineralized, and sagittally serially sectioned in a bucco-lingual direction in a microtome with a thickness of 4,5 µm. Sections were stained with a modified Brown and Benn staining for bacteria, unstained sections were analysed in field emission SEM. Results., Stained sections from the cuspal areas, below the hypomineralized enamel, the staining indicated the presence of bacteria in the dentinal tubules. The HTX staining showed that the pulp in sections without any findings was normal and free from bacteria or infiltrates from inflammatory cells. In sections where bacteria were found in the cuspal areas or deeper in the dentin, a zone of reparative dentin was found, and in sections from one tooth, the coronal pulp showed an inflammatory reaction with inflammatory cells. In sections adjacent to those without any bacterial staining, the SEM analyses revealed empty dentinal tubules without any odontoblast processes or signs of bacteria. When odontoblast processes were found, the dentinal tubules were filled with bacteria located on the surface of the odontoblast processes. In some areas, a large number of tubules were found with bacteria. No bacteria were found close to the pulp. The odontoblast processes appeared larger in areas where bacteria were found. Conclusions., The presence of bacteria in the dentinal tubules and inflammatory reactions in the pulp indicate that oral bacteria may penetrate through the hypomineralized enamel into the dentin, thus possibly contribute to hypersensitivity of teeth with MIH. [source] Comparison of BrdU and cyclin A as markers of the S-phase in oral precancerous lesionsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 9 2000Richard J. Oliver Abstract: A study comparing bromodeoxyuridine (BrdU) and cyclin A as markers of cells in the S-phase in oral precancerous lesions was performed. These were also compared with the growth fraction (GF) as assessed by Ki-67. Biopsies of 15 lesions were obtained, presenting clinically as leukoplakia or erythroplakia of the lateral tongue or floor of mouth. Half of each biopsy was incubated in BrdU and routinely fixed and processed. Sequential sections from each block were cut and stained immunohistochemically with antibodies against the following proteins: BrdU, Ki-67 and cyclin A. Stained sections were quantified and the labelling indices (LI) expressed per 100 of the total nucleated cell population (%) and per millimetre basement length (/mm). The mean LI% for BrdU was 11.24% (SD 2.83), for cyclin A it was 12.76% (SD 3.88) and the GF% was 29.25% (SD 11.88). The mean LI/mm for BrdU was 40.93/mm (SD 11.88), for cyclin A it was 47.59/mm (SD 18.28) and the GF/mm was 110.72/mm (SD 49.30). The BrdU and cyclin A indices were significantly correlated with each other. In the more dysplastic cases, the cyclin A LI was quantitatively much larger than that for BrdU, suggesting that the protein was being overexpressed. It was concluded that as a tool to study the kinetic aspects of the cell cycle in dysplastic lesions cyclin A was limited by the fact that it is overexpressed. In minimally dysplastic lesions and normal epithelia, however, cyclin A may be a viable alternative to BrdU for the study of the S-phase. [source] Cover Picture: J. Biophoton.JOURNAL OF BIOPHOTONICS, Issue 1-2 20091-2/200 Left panel: Photomicrograph, at 40× magnification, of a 1 × 1 mm stained section of axillary lymph node from a sentinel lymph node recession. The pink areas are due to the capsule, and the dark purple areas to lymphocytes. Right panel: Overlay of areas identified to contain abnormal tissue from a breast cancer metastasis via spectral imaging. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Simple non-staining method to demonstrate urate crystals in formalin-fixed, paraffin-embedded skin biopsiesJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2009Joshua Weaver Background:, Gouty tophi classically occur as nodules over joints and the helix. The ideal fixative for preservation of gout crystals has traditionally been alcohol because the crystals are formalin and water soluble. However, most biopsies are submitted in formalin fixative, which results in dissolution of urate crystals leaving behind a non-specific pale amorphous area. Although complex staining methods to show urate crystals in tissue have been described, the present study elucidates a simple non-staining method utilizing a thick unstained coverslipped microscopy slide that allows detection and confirmation of birefringence of urate crystals in formalin-fixed, paraffin-embedded tissue. Methods:, Twenty-nine cases of cutaneous gouty tophi were evaluated using a hematoxylin-eosin (H&E)-stained section, a 10-,m unstained coverslipped section and a 4-,m unstained coverslipped section. In all cases, the specimen was received and submitted in formalin. Results:, Polarizable crystals were not identified in any of the H&E sections. The use of the thicker unstained coverslipped section was more sensitive than the standard 4 ,m section by recognizing the characteristic urate crystals in 48% and 38% of the cases, respectively. Conclusions:, This inexpensive adjunctive tool can be used to document gout crystals in almost half of skin biopsies. [source] Magnetic Resonance Imaging in the Study of the Lithium,Pilocarpine Model of Temporal Lobe Epilepsy in Adult RatsEPILEPSIA, Issue 4 2002Catherine Roch Summary: ,Purpose: In temporal lobe epilepsy, it remains to be clarified whether hippocampal sclerosis is the cause or the consequence of epilepsy. We studied the temporal evolution of the lesions in the lithium,pilocarpine model of epilepsy in the rat with magnetic resonance imaging (MRI) to determine the progressive morphologic changes occurring before the appearance of chronic epilepsy. Methods: MRI was performed on an MR scanner operating at 4.7 T. We followed the evolution of lesions using T2 - and T1 -weighted sequences before and after the injection of gadolinium from 2 h to 9 weeks. Results: At 2 h after status epilepticus (SE), a blood,brain barrier breakdown could be observed only in the thalamus; it had disappeared by 6 h. At 24 h after SE, edema was present in the amygdala and the piriform and entorhinal cortices together with extensive neuronal loss; it disappeared progressively over a 5-day period. During the chronic phase, a cortical signal reappeared in all animals; this signal corresponded to gliosis, which appeared on glial fibrillary acidic protein (GFAP) immunohistochemically stained sections as hypertrophic astrocytes with thickened processes. In the hippocampus, the correlation between histopathology and T2 -weighted signal underscored the progressive constitution of atrophy and sclerosis, starting 2 days after SE. Conclusions: These data show the reactivity of the cortex that characterizes the initial step leading to the development of epilepsy and the late gliosis that could result from the spontaneous seizures. Moreover, it appears that hippocampal sclerosis progressively worsened and could be both the cause and the consequence of epileptic activity. [source] Importance of molecular analysis in detecting cervical lymph node metastasis in head and neck squamous cell carcinomaHEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 9 2006Mohamed N. Elsheikh MD Abstract Background. Because of the impact of nodal status on treatment and survival in squamous cell carcinoma of the head and neck, accurate staging of cervical lymph nodes is critical. This article explores the value of molecular analyses in the detection of cervical lymph node metastasis. Methods. A review of the literature was carried out and combined with our own experience regarding the role of molecular analyses in detecting cervical lymph node metastasis. Results. Few studies have demonstrated the diagnostic and prognostic relevance of molecular analysis in detecting tumor cells in lymph nodes. Nodal staging was improved by the use of molecular techniques; when compared with histopathologic examination, however, the small sample size of these studies did not allow definitive conclusions. Conclusions. Molecular analysis is exquisitely sensitive in detecting very small cancer deposits within lymph nodes. It provides an oncologic basis that may be used to guide therapy and influence outcomes. It should be recommended for diagnostic use in controlled studies of patients without evidence of lymph node metastasis on routine hematoxylin,eosin,stained sections. The clinical significance of these types of metastases, however, must be determined with carefully designed and controlled prospective clinical trials. © 2006 Wiley Periodicals, Inc. Head Neck, 2006 [source] Visualization of Helicobacter Species Within the Murine Cecal Mucosa Using Specific Fluorescence In Situ HybridizationHELICOBACTER, Issue 2 2005Vivian Chan ABSTRACT Background., Members of the genus Helicobacter have been associated with colitis development in a number of immunodeficient animal models. While it is known that these organisms can initiate colitis development, the location and spatial distribution of these bacteria within the intestinal tract is currently unknown. In this study, we developed and optimized fluorescence in situ hybridization (FISH) probes specifically for Helicobacter species. Materials and Methods., Based on 16S-RNA gene alignments, two probes specific for the entire family Helicobacteraceae and two probes specific for Helicobacter ganmani and Helicobacter hepaticus were designed. Evaluation of these probes was determined using ATCC reference strains and cecum samples from ten IL-10 knockout mice. The presence of Helicobacter species was determined using FISH and verified using PCR-DGGE and microscopic examination of silver stained sections. Results., Analysis of the ATCC reference strains revealed that the probes HEL274/HEL717 were specific for the family Helicobacteraceae, while HEP642 was specific for H. hepaticus and GAN1237 for H. ganmani. Using these probes, a pattern of spatial localization of the two different Helicobacter species was observed in the cecum tissues of IL-10 knockout mice. This consistently showed that H. ganmani was localized to the lower regions and H. hepaticus to the mid-upper regions of the crypts. Conclusion., We have developed FISH probes specific for the family Helicobacteraceae as well as two individual Helicobacter species. This study will allow the future use of the FISH to better understand host-pathogen interactions in vitro. [source] The diagnosis of dysplasia and malignancy in Barrett's oesophagusHISTOPATHOLOGY, Issue 2 2000REVIEW Barrett's metaplasia is associated with an increased risk for adenocarcinoma. Adenocarcinoma develops through a multistep process characterized by defects in genes and morphological abnormalities. The early morphological changes of the process are called ,dysplasia'. Dysplasia is defined as an unequivocal neoplastic (premalignant) transformation confined within the basement membrane. For most Western pathologists malignancy is defined as invasion and characterized by a breach through the basement membrane. Japanese pathologists rely on cytological atypia and complex branching of crypts. Cytological and architectural abnormalities allow identification of dysplasia on routinely stained sections. A distinction is made between low- and high-grade dysplasia. The differential diagnosis between low-grade dysplasia and reactive changes can be difficult. Therefore a second opinion is strongly recommended, not only for high-grade dysplasia but also for low-grade. Immunohistochemistry for p53 and flow cytometry for detection of aneuploidy can support the diagnosis. Identification of dysplasia and malignancy depends on the number of biopsy samples examined. The minimum number of biopsies required has not yet been determined and depends partly on the length of the metaplastic segment. It has been proposed to sample with four quadrant biopsies at 20-mm intervals. New endoscopic techniques can increase the diagnostic yield. Endoscopically visible lesions increase the risk of finding malignancy. The time sequence for the progression of dysplasia is not known but progression from low- to high-grade and cancer has been shown to occur over a period of years although it may not be inevitable. [source] The structure of dentine in the apical region of human teethINTERNATIONAL ENDODONTIC JOURNAL, Issue 5 2001I. A. Mjör Abstract Aim To study the structure of the apical region of human teeth with emphasis on dentinal tubules and their branches. Methodology This descriptive histological study employed demineralized stained sections for light microscopy, demineralized unstained sections for scanning electron microscopy, and undemineralized, acid-etched specimens for confocal tandem scanning microscopy. Results The apical portion of human teeth showed marked variations in structure, including accessory root canals, areas of resorption and repaired resorptions, occasional attached, embedded and free pulp stones, varied amounts of irregular secondary dentine, and even cementum-like tissue lining the apical root canal wall. The apex often deviated from the long axis of the root canal. Primary dentinal tubules were irregular in direction and density. Some areas were devoid of tubules. Conclusions The irregular and variable structure of the apical region of human teeth represent special challenges during endodontic therapy. Obturation techniques based on the penetration of adhesives into dentinal tubules are unlikely to be successful and adhesive techniques must depend on impregnation of a hybrid layer. [source] The amounts and deposition patterns of fibrin-type fibrinoid at the villous surface are altered in pregnancy at high altitudeJOURNAL OF ANATOMY, Issue 5 2002T. M. Mayhew In pregnancy at high altitude, there is preplacental (hypobaric) hypoxia and intrauterine fetal growth is restricted. Previous studies on placentas from Amerindian and nonindigenous women completing term pregnancies at low (LA; 400 m) and high (HA; 3600 m) altitudes in Bolivia showed that HA placentas had smaller surface areas of villi and smaller volumes of fibrin type fibrinoid (FTF). Recently we devised a stereological method for testing whether perivillous FTF (pFTF) is randomly distributed at the surface of villous trophoblast. Here the method is applied to test 2 experimental hypotheses: [1] deposition of pFTF is nonrandom regardless of altitude and [2] deposition patterns differ between altitudes. Uniform random samples of microscopical fields were drawn from Masson trichrome stained sections and intersection counts used to estimate the surface areas of, and patterns of pFTF on, 4 regions of trophoblast: nonsyncytial knots (nonSK), syncytial knots (SK), syncytial bridges (SB) and denudation sites (DEN). Absolute areas were compared by 2-way analyses of variance. Expected and observed distributions were compared by (2 and contingency table analyses. At LA the mean (SEM) volume of FTF was 8.4 (1.54) cm3 and villous surface area was 7.0 (0.43) m2. At HA FTF volume was reduced by about 50% (P < 0.01) and villous surface by 20% (P < 0.01). The surface composition of trophoblast in LA placentas was nonSK (91%), SK (5%) and SB and DEN (both less than 3%). Relative surfaces were not significantly altered in HA placentas but, due to the impoverished growth of villi at HA, the changes represented a real decline in absolute surface of nonSK. At HA, the total surface of pFTF on trophoblast decreased by about 40%, from 4430 (564) cm2,2570 (406) cm2 (P < 0.01). At both altitudes pFTF deposition was preferentially found at DEN (12-fold greater than expected for a random distribution). Pattern differences were detected between altitudes. In HA placentas the amount of pFTF deposited on nonSK regions was about 45% less (P < 0.05); apparent changes on SK and SB regions were not significant. These histometric findings suggest that the coagulation-fibrinolysis steady state is altered at HA and favours greater fibrinolysis. At least some of the fibrinolytic or anticoagulant activity seems to reside in or on thinner regions of villous trophoblast and the placenta may be a relatively privileged site in terms of fibrinolysis. Also, reduced deposition of pFTF is probably linked to changes in the steady state of trophoblast turnover which seems to be perturbed in HA pregnancies. [source] Loss of Osteocyte Integrity in Association with Microdamage and Bone Remodeling After Fatigue In Vivo,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 1 2000Olivier Verborgt Abstract As a result of fatigue, bone sustains microdamage, which is then repaired by bone-remodeling processes. How osteoclastic activity is targeted at the removal of microdamaged regions of bone matrix is unknown. In the current studies, we tested the hypothesis that changes in osteocyte integrity, through the initiation of regulated cell death (apoptosis), are associated with fatigue-related microdamage and bone resorption. Ulnae of adult rats were fatigue-loaded to produce a known degree of matrix damage. Osteocyte integrity was then assessed histomorphometrically from terminal deoxynucleotidyl transferase,mediated deoxyuridine triphosphate,nick end labeling (TUNEL),stained sections to detect cells undergoing DNA fragmentation associated with apoptosis; toluidine blue,stained sections were used for secondary morphological confirmation. Ten days after loading, large numbers of TUNEL-positive osteocytes were found in bone surrounding microcracks and in bone surrounding intracortical resorption spaces (,300% increases over controls, p < 0.005). TUNEL labeling in loaded ulnae at sites distant from microcracks or resorption foci did not differ from that in control bone. Osteocytes in toluidine blue,stained sections showed equivalent trends to TUNEL-stained sections, with significant increases in pyknotic nuclei and empty lacunae associated with microcracks and intracortical resorption spaces. TUNEL-positive osteocytes were observed around bone microdamage by 1 day after loading (p < 0.01 relative to baseline), and their number remained elevated throughout the entire experimental period. Increases in empty lacunae and decreases in normal osteocyte numbers were observed over time as well. These studies show that (1) osteocyte apoptosis is induced by bone fatigue, (2) this apoptosis is localized to regions of bone that contain microcracks, and (3) osteoclastic resorption after fatigue also coincides with regions of osteocyte apoptosis. The strong associations between microdamage, osteocyte apoptosis, and subsequent bone remodeling support the hypothesis that osteocyte apoptosis provides a key part of the activation or signaling mechanisms by which osteoclasts target bone for removal after fatigue-induced matrix injury. [source] Deproteinized cancellous bovine bone (Bio-Oss®) as bone substitute for sinus floor elevationJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 3 2003A retrospective, histomorphometrical study of five cases Abstract Objectives: To study in detail the performance of deproteinized cancellous bovine bone (DPBB, Bio-Osso®) granules as a bone substitute, a histomorphometric was performed on five patients treated with DPBB for reconstruction of the severely atrophic maxilla. Material and Methods: DPBB was used as mixture with autogenous bone particles, in concentrations that increased from 20% to 100% DPBB, with the time of healing increasing accordingly from 5 to 8 months. A total of 20 vertical biopsies was taken at the time of fixture installation and used for histomorphometry as undecalcified Goldner stained sections. Results: The results show that in all cases, the DPBB granules had been interconnected by bridges of vital newly formed bone. The volume of bone in the grafted area correlated inversely with the concentration of DPBB grafted, and varied between 37% and 23%. However, the total volume of mineralized material (bone plus DPI3B granules) remained within the same range in all five patients (between 53% and 59%). The high values for osteoid and resorption surface, and the presence of tartrate-resistant acid phosphatase-positive multinucleated osteoclasts in resorption lacunae, indicated that bone remodeling was very active in all grafts. Osteoclasts were also observed in shallow resorption pits on DPBB surfaces. The percentage DPBB surface in contact with bone remained stable at about 35% and could not be related to the proportion of DPBB grafted. Conclusion: Although the number of patients examined was limited, the data suggest that deproteinized cancellous bovine bone, preferably combined with autogenous bone particles, is a suitable material for sinus floor elevation in the severely atrophic human maxilla. Zusammenfassung Ent-Proteinisierter spöngiöser boviner Knochen (Bio-Oss) als Knochenersatz zur Sinusboden-Elevation. Eine retrospektive histomorphometrische Studie an 5 Fällen. Ziele:Um das Verhalten Ent-Proteinisierten spöngiösen bovinen Knochengranulats (DPBB, Bio,Oss) als Knochenersatzmaterial detailliert zu studieren, wurde an 5 Patienten, die mit DPBB zur Rekonstruktion der stark atrophischen Maxilla behandelt wurden, eine histomorphometrische Studie durchgeführt. Material und Methoden:DPBB wurde als Mischung mit autogenen Knochenpartikeln in einer Konzentration von 20 , 100% DPBB verwendet. Die Heilungsdauer wurde entsprechend von 5 auf 8 Monate erhöht. Zum Zeitpunkt der Implantatsetzung wurden insgesamt 20 vertikale Biopsien entnommen und für die Histomorphometrie als nicht-entkalkte, Goldner-gefärbte Schnitte verwendet. Ergebnisse: Die Ergebnisse zeigten in allen Fällen, dass die DPBB-Granula über Brücken von vitalem neu gebildetem Knochen miteinander verbunden waren. Das Volumen des Knochens in dem transplantiertem Gebiet korrelierte umgekehrt mit der Konzentration der transpantierten DPBB und variierte zwischen 37% und 23%. Jedoch lag das Gesamtvolumen des mineralisierten Materials (Knochen+DPBB-Granula)bei allen 5 Patienten im selben Bereich (zwischen 53% und 59%). Die hohen Werte für Ostoid und Resorptionsflächen sowie die Anwesenheit von TRAP-positiven multinukleären Osteoklasten in Resorptionslakunen, zeigte, dass das Knochenremodelling in allen Transplantaten sehr aktiv war. Auch in flachen Resorpionsgrübchen auf der DPBB-Oberfläche wurden Osteoklasten beobachtet. Der Prozentsatz der DPBB-Oberfläche welche im Knochenkontakt war blieb mit etwa 35% stabil und korrelierte nicht mit dem Anteil des transplantierten DPBBs. Schlussfolgerung:Obwohl die untersuchte Patientenzahl sehr gering ist, lassen die Daten vermuten, dass Ent-Proteinisierter spöngiöser boviner Knochen, vorzugsweise mit autogenen Knochenpartikeln kombiniert, ein geeignetes Material für die Sinusboden-Elevation bei stark atrophischer Maxilla ist. Résumé Os bovin spongieux déprotéiné comme substitut osseux dans l'épaississement sinusal. Une étude histomorphométrique rétrospective de cinq cas Le but de cette étude a été d'analyser en détail les performances de l'os bovin spongieux déprotéiné (DPBB, Bio-Oss®) en granules comme substitut osseux par une analyse histomorphométrique effectuée chez cinq patients traités pour une reconstruction au niveau d'un maxillaire sévèrement atrophié. DPBB a été utilisé en mélange avec des particules osseuses autogènes en concentrations augmentaient de 20 à 100% de DPBB, avec un temps de guérison augmentant paralèllement de cinq à huit mois. Vingt biopsies verticales ont ainsi été prélevées au moment du placement des implants et utilisées pour l'histomorphométrie sur coupes colorées Goldner non-décalcifiées. Les résultats ont indiqué que dans tous les cas les granules DPBB ont été interconnectées par des bridges d'os néoformé vivant. Le volume d'os dans l'aire greffée était en corrélation inverse avec les concentrations de DPBB greffées et variait entre 37 et 23 %. Cependant le volume total de matériel minéralisé (os+granules DPBB) restait dans les mêmes moyennes chez les cinq patients (entre 53 et 59 %). Les valeurs importantes pour la surface de résorption et ostéides, et la présence d'ostéoclastes multinucléaires positifs au TRAP dans les lacunes de résorption indiquaient que le remodelage osseux était très actif dans tous les greffons. Les ostéoclastes étaient également observés dans des petites crevasses de résorption étroites sur les surfaces DPBB. Le pourcentage DPBB en contact avec l'os demeurait stable à environ 35% et ne pouvait pas être mis en relation avec la proportion de DPBB greffé. Bien que le nombre de patients examinés aie été très limité, les données suggèrent que l'os bovin spongieux déprotéiné de préférence en combinaison avec des particules d'os autogène est un bon matériel pour l'épaississement du plancher sinusal en présence de maxillaire humain sévèrement atrophié. [source] An unusual dematiaceous fungal infection of the skin caused by Fonsecaea pedrosoi: a case report and review of the literatureJOURNAL OF CUTANEOUS PATHOLOGY, Issue 5 2003Sate H. Hamza Background:, A case of an unusual dematiaceous fungal infection of the skin in a 43-year-old man with diabetes mellitus treated with steroids for reactive airway disease is presented. He developed chromoblastomycosis in the left wrist and was treated with antifungals and multiple surgical excisions. Results:, Histologic examination of the excised tissue revealed widespread suppurative granulomatous inflammation in the dermis and subcutaneous tissue. Thick-walled internally septated brown fungal cells were found both inside multinucleated giant cells and extracellularly. Non-to-lightly pigmented septate hyphal elements, however, were also identified with special stains and, in retrospect, on one of the routinely stained sections. In culture, the organism was reported to initially grow as soft white colonies that soon turned to black and velvety. Conclusions:, The two unusual features of this case include the controversial report of the organism's initial growth in culture as soft white colonies and the presence of hyphal elements in addition to the sclerotic bodies in the dermis and subcutaneous tissue. This has not been reported before in human cases of dermal infection by Fonsecaea pedrosoi. [source] Investigation of mechanisms underlying transient T2 normalization in longitudinal studies of ischemic strokeJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 2 2002Shao-Pow Lin PhD Abstract Purpose To determine if the phenomenon of transient normalization of T2 relaxation in the subacute stage of ischemic stroke is associated with either magnetic susceptibility effects secondary to hemorrhage or changes in tissue water content. Materials and Methods We utilized a rat model of transient, focal, cerebral ischemia. The possibility of hemorrhage was evaluated with T2*-weighted (T2*W) imaging and histology. Changes in water content were assessed by brain wet-to-dry weight. Results Susceptibility effects were not evident in T2*W images, and neither red blood cells nor unchelated Fe(III) was found in hematoxylin and eosin (H-E), or Prussian Blue,stained sections, respectively. However, between the peak of T2 contrast and the point of transient T2 normalization, water content consistently decreased by an average of 3%. Conclusion Transient T2 normalization is associated with normalization of water content and can occur without evidence of hemorrhage. J. Magn. Reson. Imaging 2002;15:130,136. © 2002 Wiley-Liss, Inc. [source] Influence of subcutaneous administration of recombinant TNF-, on ligature-induced periodontitis in ratsJOURNAL OF PERIODONTAL RESEARCH, Issue 2 2003Rok Ga Proinflammatory cytokine tumor necrosis factor alpha (TNF-,) was found in inflamed periodontal tissues and many studies pointed to its significant role in development of periodontal disease. In this study, the influence of subcutaneously administered recombinant human TNF-, (rhTNF-,) on inflammatory reaction and periodontal breakdown in rats was analyzed during experimental periodontitis, induced by placing silk ligatures around the maxillary right second molar tooth. The rats were divided into two groups with five animals in each; the first group was infused subcutaneously with rhTNF-, via osmotic pumps for 2 weeks and the second group was infused with phosphate-buffered saline (PBS) in the same manner. Inflammatory reaction and periodontal breakdown was evaluated morphometrically on hematoxylin and eosin stained sections. Serum ionized calcium and inorganic phosphates were monitored colorimetrically. Serum calcium and phosphate levels were similar in rats receiving rhTNF-, and PBS. Ligation resulted in accelerated periodontal breakdown, while subcutaneous rhTNF-, administration by itself had no significant effect. Combined effect of subcutaneous rhTNF-, administration and ligation resulted in a significantly greater inflammatory reaction and periodontal breakdown then either treatment alone. We concluded that the subcutaneous administration of rhTNF-, accelerates the progression of experimental periodontitis in rats. [source] Comparison of extent of tau pathology in patients with frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17), frontotemporal lobar degeneration with Pick bodies and early onset Alzheimer's diseaseNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 4 2006A.-M. Shiarli In order to gain insight into the pathogenesis of frontotemporal lobar degeneration (FTLD), the mean tau load in frontal cortex was compared in 34 patients with frontotemporal dementia linked to chromosome 17 (FTDP-17) with 12 different mutations in the tau gene (MAPT), 11 patients with sporadic FTLD with Pick bodies and 25 patients with early onset Alzheimer's disease (EOAD). Tau load was determined, as percentage of tissue occupied by stained product, by image analysis of immunohistochemically stained sections using the phospho-dependent antibodies AT8, AT100 and AT180. With AT8 and AT180 antibodies, the amount of tau was significantly (P < 0.001 in each instance) less than that in EOAD for both FTDP-17 (8.5% and 10.0% respectively) and sporadic FTLD with Pick bodies (16.1% and 10.0% respectively). With AT100, the amount of tau detected in FTDP-17 was 54% (P < 0.001) of that detected in EOAD, but no tau was detected in sporadic FTLD with Pick bodies using this particular antibody. The amount of insoluble tau deposited within the brain in FTDP-17 did not depend in any systematic way upon where the MAPT mutation was topographically located within the gene, or on the physiological or structural change generated by the mutation, regardless of which anti-tau antibody was used. Not only does the amount of tau deposited in the brain differ between the three disorders, but the pattern of phosphorylation of tau also varies according to disease. These findings raise important questions relating to the role of aggregated tau in neurodegeneration , whether this represents an adaptive response which promotes the survival of neurones, or whether it is a detrimental change that directly, or indirectly, brings about the demize of the affected cell. [source] Genetic,morphologic association study: association between the low density lipoprotein-receptor related protein (LRP) and cerebral amyloid angiopathyNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 1 2005M. Christoforidis Accumulating evidence suggests that genetic factors such as apolipoprotein E (APOE), can act in different ways in the pathogenesis of cerebral amyloid angiopathy (CAA) and Alzheimer's disease (AD). The role of the low-density lipoprotein-receptor related protein (LRP), the major cerebral APOE receptor, in AD has been discussed controversially depending on data from different populations and methodological approaches. We examined the influence of LRP polymorphisms on CAA in 125 post-mortem cases genotyped for APOE and classified according to the neurofibrillary Braak and Braak staging of AD (indicating neurodegeneration grade). CAA was assessed separately for leptomeningeal (CAAlep.), noncapillary cortical (CAAcort.) and capillary cortical (CAAcap.) vessels in ,-amyloid stained sections. Our results suggest: (i) the 87 bp allele of LRP5, polymorphism (LRP5,) is an independent predictive factor for CAAcort. and CAAlep.; (ii) the C/C genotype (C allele) of the LRP exon 3 polymorphism is positively associated with, the, severity, of, CAAlep., and, CAAcort.,, implicating a younger age of CAA onset and/or faster CAA progression; (iii) as CAAcort. and CAAlep. showed different genetic associations in contrast to CAAcap., we can underscore the hypothesis that different molecular mechanisms are involved in CAA pathogenesis of noncapillary and capillary cerebral vessels. Our results lead us to postulate that the LRP5,87 bp and the LRP exon 3 C alleles of the LRP gene (or another locus that might be in linkage disequilibrium with these LRP polymorphic sites) could modify cerebrovascular LRP function or expression in noncapillary cerebral vessels, leading to an increased cerebrovascular amyloid deposition. [source] Isolation of a Thermotolerant Paravahlkampfia sp. from Lizard Intestine: Biology and Molecular IdentificationTHE JOURNAL OF EUKARYOTIC MICROBIOLOGY, Issue 5 2003FREDERICK L. SCHUSTER ABSTRACT. An amoeba was isolated from the intestines of several moribund pink-tongued skinks (lizards), Hemisphaeriodon ger-rardi Unusual features of this isolate were its ability to grow at temperatures of , 37 °C, and its inability to use Escherichia coli as a food source or to grow axenically on a variety of enriched culture media suitable for other soil amoeba isolates. Growth was abundant, however, on tissue culture cells, with amoebae clearing cell monolayers in ,48 h at 37 °C. Trophozoites had a vahlkampfiid-like morphology, moving by means of an anterior eruptive pseudopod. Cysts, round to slightly ovoid and lacking exit pores, were formed in culture. Tests for enflagellation of trophic amoebae were negative. Indirect immunofluorescence staining was negative for Naegleria fowleri and Willaertia sp. The isolate was sensitive to azithromycin, but not to amphotericin B, pentamidine isethionate, fluconazole, 5-fluorocytosine, and sulfadiazine. Phylogenetic analysis based on the PCR-amplified small subunit ribosomal DNA, identified the organism as Paravahlkampfia ustiana, an amoeba not previously isolated from either poikilothermic or homeothermic hosts. No evidence of pathology was seen in stained sections of lizard intestine, suggesting that the ameba was part of the normal fauna of the lizard gut. Its diet in the lizard intestine is unknown and the organism may have unusual growth requirements. Thus, P. ustiana joins other soil amoebae that have been isolated from mammals, amphibia, fish, and reptiles, which have the potential of becoming opportunistic pathogens. [source] Combining angiogenic gene and stem cell therapies for myocardial infarctionTHE JOURNAL OF GENE MEDICINE, Issue 9 2009Jennifer Pons Abstract Background Transplantation of stem cells from various sources into infarcted hearts has the potential to promote myocardial regeneration. However, the regenerative capacity is limited partly as a result of the low survival rate of the transplanted cells in the ischemic myocardium. In the present study, we tested the hypothesis that combining cell and angiogenic gene therapies would provide additive therapeutic effects via co-injection of bone marrow-derived mesenchymal stem cells (MSCs) with an adeno-associated viral vector (AAV), MLCVEGF, which expresses vascular endothelial growth factor (VEGF) in a cardiac-specific and hypoxia-inducible manner. Methods MSCs isolated from transgenic mice expressing green fluorescent protein and MLCVEGF packaged in AAV serotype 1 capsid were injected into mouse hearts at the border of ischemic area, immediately after occlusion of the left anterior descending coronary, individually or together. Engrafted cells were detected and quantified by real-time polymerase chain reaction and immunostaining. Angiogenesis and infarct size were analyzed on histological and immunohistochemical stained sections. Cardiac function was analyzed by echocardiography. Results We found that co-injection of AAV1-MLCVEGF with MSCs reduced cell loss. Although injection of MSCs and AAV1-MLCVEGF individually improved cardiac function and reduced infarct size, co-injection of MSC and AAV1-MLCVEGF resulted in the best improvement in cardiac function as well as the smallest infarct among all groups. Moreover, injection of AAV1-MLCVEGF induced neovasculatures. Nonetheless, injection of MSCs attracted endogenous stem cell homing and increased scar thickness. Conclusions Co-injection of MLCVEGF and MSCs in ischemic hearts can result in better cardiac function and MSC survival, compared to their individual injections, as a result of the additive effects of each therapy. Copyright © 2009 John Wiley & Sons, Ltd. [source] Increased Expression of Laminin-5 and Its Prognostic Significance in Hypopharyngeal Cancer,THE LARYNGOSCOPE, Issue 7 2004Meijin Nakayama MD Objectives: We investigated the clinicopathologic significance of laminin-5 ,2 chain (LN,2) expression in 26 surgically removed hypopharyngeal cancers and compared the results with conventional prognostic factors elicited from hematoxylin-eosin (H&E) stained whole-mount laryngeal sections. Study Design: Stainability of LN,2 was mainly evaluated at the invasive front of the cancer nests. Scoring was performed on the basis of a semiquantitative scale defined according to the number of immunopositive cancer cells (score 3, 2, 1, and 0). Stainability of LN,2 was also evaluated macroscopically at different tumor locations such as surface center, interstitial space, and invasive front. Status of cartilage and vascular invasion and patterns of tumor extension were evaluated from H&E stained sections. The results of LN,2 expression correlated with the tumor stages, neck node status, pathologic differentiation, and prognoses. Results: Among the 26 cases, 24 demonstrated positive LN,2 expression. Of these cases, 1, 14, 9, and 0 showed scores of 3, 2, 1, and 0, respectively. Positive expression of LN,2 at the invasive front was more prominent in the high-expression group, and surface center was often positive in the cases of low-expression group. Among the H&E stained prognostic factors, vascular invasion and infiltrative pattern demonstrated significant correlations with clinical outcome. Vascular invasion and infiltrative pattern were also closely related to positive LN,2 expression. Five-year survival rates of patients who showed high LN,2 expression were significantly poorer than in patients with low expression. Conclusion: Hypopharyngeal cancers positive for LN,2 indicate a considerable risk for cancer progression and are closely related to prognosis. Increased LN,2 expression might be a prognostic indicator for squamous cell carcinomas of the hypopharynx. [source] Increased neuronal cell number in the dorsal motor nucleus of the vagus in schizophreniaACTA NEUROPSYCHIATRICA, Issue 1 2010Hubertus Axer Axer H, Bernstein H-G, Keiner S, Heronimus P, Sauer H, Witte OW, Bogerts B, Bär K-J. Increased neuronal cell number in the dorsal motor nucleus of the vagus in schizophrenia. Objective: Recently, a reduction in efferent vagal regulation has been found in schizophrenic patients. Methods: Therefore, the brainstems of nine schizophrenic patients and nine normal controls were stereologically analysed. The number of neurons using the optical fractionator method and nuclear volumes applying the Cavalieri principle was estimated in Nissl stained sections of the dorsal motor nucleus of the vagus (DMNV) and the hypoglossal nucleus. Results: The neurons in the right DMNV were significantly increased in the schizophrenic group compared to normal controls (p = 0.047), while the volumes of the DMNV did not differ. In contrast, no such differences were found in the hypoglossal nucleus. Conclusion: Although this pilot study is limited by its small sample size, the analysis of the solitarius,ambiguus,vagus system in schizophrenic patients is an interesting target in schizophrenia research. The most reasonable background for increased neuron numbers in the DMNV could be a system-specific neurodevelopmental disturbance in schizophrenia. [source] Optical Coherence Tomography: A Noninvasive Method to Assess Wound ReepithelializationACADEMIC EMERGENCY MEDICINE, Issue 5 2007Adam J. Singer MD BackgroundAccurate assessment of wound healing may require invasive tissue biopsies, limiting its clinical usefulness in humans. Optical coherence tomography (OCT) is a novel, high-resolution method using light reflection to obtain noninvasive cross sectional imaging of biological tissues. ObjectivesTo evaluate the utility of OCT for assessing wound reepithelialization in a porcine model. MethodsThe authors conducted an animal study with two domestic pigs. Excisional cutaneous wounds were created over the ventral surface of the animals using an electric dermatome set at a depth of 600 ,m. The wounds were excised two or three days later and precisely marked to guide initial OCT and subsequent tissue slicing and microscopy. Comparing hematoxylin and eosin,stained histologic sections and the corresponding OCT images from each tissue sample permitted identification of the correlative micromorphology. Scatter and Bland,Altman plots were used to present the data. The primary measure of agreement was the standard deviation of the pairwise differences in percent reepithelialization between OCT and histology together with a 95% confidence interval. ResultsIn normal skin, the epidermis was characterized by a thin, bright layer indicating a high degree of light scattering on OCT. The dermis below was characterized by a thicker, darker area indicating less scattering of light. All fresh excisional wounds lacked an outer bright layer of epidermis immediately after injury. At days 2 and 3, the wounds were partially reepithelialized. A new bright layer with intense light scattering was present on OCT corresponding to the neoepidermis on hematoxylin and eosin,stained sections. The correlation between percent reepithelialization measured with OCT and histology was 0.66 (p < 0.001), and the standard deviation of the differences was 11.0% (95% confidence interval = 8.4% to 16.1%). ConclusionsOCT accurately detects the presence or absence of the epidermal layer of skin, allowing noninvasive tracking of wound reepithelialization. [source] | ||||||||||||||||||||||||||||