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Light Microscopic Examination (light + microscopic_examination)
Selected AbstractsNetrin-G2 and netrin-G2 ligand are both required for normal auditory responsivenessGENES, BRAIN AND BEHAVIOR, Issue 4 2008W. Zhang Mice in which netrin-G2 has been genetically inhibited do not startle to an acoustic stimulus, but otherwise perform normally through a behavioral test battery. Light microscopic examination of the inner ear showed no obvious structural abnormalities. Brainstem responses to acoustic stimuli (auditory brainstem responses, ABR) were also present, confirming the lack of any overarching defects in the inner ear or auditory nerve. Genetic inhibition of netrin-G2 ligand produced a nearly identical phenotype, that is, no startle with ABR present, and otherwise normal. This similarity confirms that these two proteins act in the same biological pathway. We have also determined that the affinity between the two proteins is strong, around 2.5 nm, similar to that observed between netrin-G1 and netrin-G1 ligand , 2.3 nm in our hands. The combination of equivalent phenotypes when genetically inhibited coupled with evidence of a strong biochemical interaction supports the notion of a receptor,ligand interaction between these two proteins in vivo. This interaction is critical for auditory synaptic responsiveness in the brain. [source] Morphological features of Murray Valley encephalitis virus infection in the central nervous system of swiss miceINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 1 2000Vance Matthews We have examined the histological and ultrastructural features of CNS infection with Murray Valley encephalitis (MVE) virus in mice inoculated with a virulent parental strain (BH3479). Light microscopic examination revealed neuronal necrosis in the olfactory bulb and hippocampus of MVE-infected brains by 5 days post-infection (pi). Electron microscopy of these regions showed endoplasmic reticulum membrane proliferation, and tubular and spherical structures in the cisternae of the endoplasmic reticulum, Golgi complex and nuclear envelope. At seven to eight days pi, infected neurones exhibited chromatin condensation and extrusion, nuclear fragmentation, loss of segments of the nuclear envelope, reduced surface contact with adjacent cells and loss of cytoplasmic organelles. This cell injury was particularly noticeable in the proximal CA3 and distal CA1 regions of the hippocampus. The inflammatory cell profile consisted of macrophages, lymphocytes and especially neutrophils, and many of these inflammatory cells were apoptotic. High mortality rates in the BH3479-infected population of mice correlated with the intense polymorphonuclear and mononuclear leucocyte inflammatory infiltrate in the CNS. [source] Characterization of cartilagenous tissue formed on calcium polyphosphate substrates in vitroJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 3 2002Stephen D. Waldman Abstract Successful joint resurfacing by tissue-engineered cartilage has been limited, in part, by an inability to secure the implant to bone. To overcome this, we have developed the methodology to form a cartilage implant in vitro consisting of a layer of cartilagenous tissue overlying a porous, biodegradable calcium polyphosphate (CPP) substrate. As bone will grow into the CPP after implantation, it will result in anchorage of the cartilage. In this study, the cartilagenous tissue formed in vitro after 8 weeks in culture was characterized and compared to native articular cartilage. Light microscopic examination of histological sections showed that there was a continuous layer of cartilagenous tissue on, and integrated with the subsurface of, the CPP substrate. The in vitro -formed tissue achieved a similar thickness to native articular cartilage (mean ± SEM: in vitro = 0.94 ± 0.03 mm; ex vivo = 1.03 ± 0.01 mm). The cells in the in vitro -formed tissue synthesized large proteoglycans (Kav ± SEM: in vitro = 0.27 ± 0.01; ex vivo = 0.27 ± 0.01) and type II collagen similar to the chondrocytes in the ex-vivo cartilage. The in vitro -formed tissue had a similar amount of proteoglycan (GAG ,g/mg dry wt.: in vitro = 198 ± 10; ex vivo = 201 ± 13) but less collagen than the native cartilage (hydroxyproline ,g/mg dry wt.: in vitro = 21 ± 1; ex vivo = 70 ± 8). The in vitro -formed tissue had only about 3% of the load-bearing capacity and stiffness of the native articular cartilage, determined from unconfined mechanical compression testing. Although low, this was within the range of properties reported by others for tissue-engineered cartilage. It is possible that the limited load-bearing capacity is the result of the low collagen content and further studies are required to identify the conditions that will increase collagen synthesis. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62:323,330, 2002 [source] A Girl with Loose Anagen Hair Syndrome and Uncombable, Spun-glass HairPEDIATRIC DERMATOLOGY, Issue 3 2005Abigail J. Lee MC A hair pull test revealed that hairs could be easily and painlessly extracted. Light microscopic examination of the hair demonstrated anagen hairs with a ruffled cuticle and distorted bulb as well as an unusual undulation and grooving of the shafts. These findings are consistent with both loose anagen and uncombable hair syndromes. The occurrence of both syndromes in the same patient seems unlikely, and we propose that our patient has loose anagen hair syndrome with features resembling uncombable hair syndrome. [source] A case of generalized argyria after ingestion of colloidal silver solutionAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 3 2009Yangho Kim Abstract A 58-year-old woman was referred to our hospital due to progressive skin darkening, which began 5 months previously. The patient had strikingly diffuse blue-gray discoloration of the skin, most prominent in sun-exposed areas, especially her face and hands. The oral mucosa, tongue, gums, eye conjunctiva, ears, nail beds, and trunk were also involved. Bluish-gray discoloration of all nails was aggravated by cold weather. She had ingested 1 L of colloidal silver solution daily for approximately 16 months as a traditional remedy. Her serum silver concentration was 381 ng/ml which was a very high (reference level: <15 ng/ml). Light microscopic examination of a punch biopsy specimen from her nose revealed fine, minute, round, and brown-black granules deposited in the basement membrane of hair follicular epithelium. Scanning electron microscopic examination showed electron-dense granules deposited in the intercellular space of sweat glands. Energy disperse X-ray spectrometry analysis demonstrated peaks for silver and sulfur in the dense black deposits. The ingestion of colloidal silver appears to be an increasing practice among patients using alternative health practices. All silver-containing products including colloidal silver should be labeled with a clear warning to prevent argyria, especially in alternative health practices. Am. J. Ind. Med. 52:246,250, 2009. © 2008 Wiley-Liss, Inc. [source] Histopathology of Pleomorphic Adenoma in the Parotid Gland: A Prospective Unselected Series of 100 Cases,THE LARYNGOSCOPE, Issue 12 2001Eberhard Stennert MD Abstract Objectives/Hypothesis Histopathological characteristics of pleomorphic adenomas, especially of capsular alterations such as thin capsule areas, capsule-free regions, capsule penetration, satellite nodules, and pseudopodia in the different subtypes, are described. Study Design Prospective unselected series of 100 consecutive cases from 1997 to 2000. Methods Light microscopic examination and semiquantitative analysis of the pleomorphic adenomas. Results Fifty-one (51%) pleomorphic adenomas were classified as myxoid (stroma-rich) type, 35 (35%) specimens as cellular type, and 14 (14%) as classic subtype. Ninety-seven percent of all tumors showed areas with thin (<20 ,m) capsule independent of the tumor subtype. Tumors of myxoid subtype showed the absolute greatest regions of a thin capsule. Especially, tumors of myxoid type (71%) often had a distinct focal absence of encapsulation with tumor merging into normal parotid gland tissue; 11% of the cellular subtype and 43% of the classic subtype presented capsule-free areas. Thirty-three percent of the myxoid pleomorphic adenomas, 23% of the cellular subtype, and 21% of the classic subtype had satellite nodules or pseudopodia. Conclusions Almost all pleomorphic adenomas have focally thin capsules. One-fourth of all pleomorphic adenomas contain abnormalities such as satellite nodules or pseudopodia. More than two-thirds of pleomorphic adenomas of the myxoid (stroma-rich) subtype and at least half of all tumors show a focal absence of the capsule. Therefore, enucleation or local dissection of the pleomorphic adenoma is not a sufficient surgical treatment of this special tumor entity. We recommend, depending on the location of the tumor, a lateral or total parotidectomy as the treatment of choice. [source] Preventive Effects of Quercetin against Benzo[a]pyrene-Induced DNA Damages and Pulmonary Precancerous Pathologic Changes in MiceBASIC AND CLINICAL PHARMACOLOGY & TOXICOLOGY, Issue 6 2006Nian-zu Jin In this study, mice in quercetin-treated groups were given quercetin for 90 days. After one week of treatment, mice in the quercetin-treated groups and the positive control group received a single intraperitoneal dose of benzo[a]pyrene (100 mg/kg body weight). The results of single cell gel electrophoresis assay showed that the average lengths of the comet cell tail and DNA damage in the peripheral blood lymphocytes of mice induced by benzo[a]pyrene decreased significantly as a result of quercetin treatment dose-dependently. Light microscopic examination showed that the degrees of pulmonary precancerous pathologic changes in the quercetin-treated groups decreased significantly compared with those in the positive control group. Meanwhile, the cytochrome P4501A1-linked 7-ethoxyresorufin O-dealkylase activities in lung microsomes of mice decreased as the dose of quercetin increased. The results of this in vivo study revealed that quercetin had a significant preventive effect on benzo[a]pyrene-induced DNA damage, and had a potential chemopreventive effect on the carcinogenesis of lung cancer induced by benzo[a]pyrene. The mechanism of these effects of quercetin could be related to the inhibition of cytochrome P4501A1 activity. [source] Dystrophia Smolandiensis: a novel morphological picture of recurrent corneal erosionsACTA OPHTHALMOLOGICA, Issue 4 2010Björn Hammar Abstract. Purpose:, The aim of this study was to describe morphological changes in Dystrophia Smolandiensis, a corneal disease that is characterized by recurrent corneal erosive episodes and the formation of central corneal keloid-like opacities in approximately half of those affected. Methods:, The corneas of seven affected individuals were examined using in-vivo confocal microscopy. Specimens of one primary corneal graft, one regraft and one biopsied keloid-like region , all obtained from members of a large family with the disease , were re-examined with a light microscope. Sections were stained with Congo red and analysed immunohistochemically for fibronectin and S100A4. Results:, Light microscopic examination revealed epithelial hyperplasia, absence of Bowman's layer and subepithelial fibrosis. Fibronectin was expressed in the area of subepithelial fibrosis, and the keratocytes in this area generally expressed S100A4. The biopsy specimen stained positive for Congo red, suggesting an amyloid deposit. In-vivo confocal microscopy confirmed epithelial abnormalities, loss of Bowman's layer and significant alterations of the subbasal nerve plexus in affected individuals. Conclusion:, The morphological picture in Dystrophia Smolandiensis is novel for a condition dominated by recurrent corneal erosions at the clinical level. Although no single morphological feature unique to the disease could be found, the general morphological pattern of pathology (true keloid formation, absence of Bowman's layer, subepithelial fibrosis and abnormal subbasal nerves) probably reflects a novel phenotypic expression of the healing response to recurrent erosion of the corneal epithelium. However, the pathogenesis of Dystrophia Smolandiensis remains to be elucidated fully. [source] Time course of bleomycin-induced lung fibrosisINTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 3 2002G. Izbicki Summary. Intratracheal instillation (IT) of bleomycin is a widely used experimental model for lung fibrosis. In this study we describe the time-course of bleomycin-induced lung fibrosis in mice using computer-assisted morphometry. C57Bl/6J mice were treated with a single IT dose of bleomycin or control saline. Animals were killed 3, 6, 14 and 21 days post-IT. Lung injury was evaluated by analysis of bronchoalveolar lavage (BAL) fluid, hydroxyproline concentration in the lung, routine light microscopic examination resulting in a semiquantitative morphological index (SMI) of lung injury, and quantitative morphological measurements (fibrosis fraction and alveolar wall area fraction) aided by optimas image analysis software. Changes in BAL fluid attributed to bleomycin treatment include increased total cell count (days 14 and 21), and increased percentage of neutrophils (days 3 and 6) followed by a sustained increase in lymphocytes (days 6, 14 and 21). Hydroxyproline levels increased in bleomycin-treated mice on days 14 and 21. Median SMI grades were significantly elevated on days 3, 14 and 21. Computer-assisted morphometry demonstrated a 3-fold increase in fibrosis fraction and a 1.3-fold increase in wall area fraction in bleomycin-treated mice on day 14, with no further increase on day 21. These data also demonstrate that the most suitable time point for assessing lung fibrosis in this model is 14 days after IT instillation of bleomycin, based on the observation that at 14 days the animals developed extensive fibrosis, but had less variability in the fibrotic response and lower mortality than later at 21 days. Computer-assisted morphometry provides objective and quantitative measurements that are a useful tool for the evaluation of bleomycin-induced lung injury. [source] Magnetic Resonance Microscopy Defines Ethanol-Induced Brain Abnormalities in Prenatal Mice: Effects of Acute Insult on Gestational Day 7ALCOHOLISM, Issue 1 2010Elizabeth A. Godin Background:, This magnetic resonance microscopy (MRM)-based report is the second in a series designed to illustrate the spectrum of craniofacial and central nervous system (CNS) dysmorphia resulting from single- and multiple-day maternal ethanol treatment. The study described in this report examined the consequences of ethanol exposure on gestational day (GD) 7 in mice, a time in development when gastrulation and neural plate development begins; corresponding to the mid- to late third week postfertilization in humans. Acute GD 7 ethanol exposure in mice has previously been shown to result in CNS defects consistent with holoprosencephaly (HPE) and craniofacial anomalies typical of those in Fetal Alcohol Syndrome (FAS). MRM has facilitated further definition of the range of GD 7 ethanol-induced defects. Methods:, C57Bl/6J female mice were intraperitoneally (i.p.) administered vehicle or 2 injections of 2.9 g/kg ethanol on day 7 of pregnancy. Stage-matched control and ethanol-exposed GD 17 fetuses selected for imaging were immersion fixed in a Bouins/Prohance solution. MRM was conducted at either 7.0 Tesla (T) or 9.4 T. Resulting 29 ,m isotropic spatial resolution scans were segmented and reconstructed to provide 3D images. Linear and volumetric brain measures, as well as morphological features, were compared for control and ethanol-exposed fetuses. Following MRM, selected specimens were processed for routine histology and light microscopic examination. Results:, Gestational day 7 ethanol exposure resulted in a spectrum of median facial and forebrain deficiencies, as expected. This range of abnormalities falls within the HPE spectrum; a spectrum for which facial dysmorphology is consistent with and typically is predictive of that of the forebrain. In addition, other defects including median facial cleft, cleft palate, micrognathia, pituitary agenesis, and third ventricular dilatation were identified. MRM analyses also revealed cerebral cortical dysplasia/heterotopias resulting from this acute, early insult and facilitated a subsequent focused histological investigation of these defects. Conclusions:, Individual MRM scans and 3D reconstructions of fetal mouse brains have facilitated demonstration of a broad range of GD 7 ethanol-induced morphological abnormality. These results, including the discovery of cerebral cortical heterotopias, elucidate the teratogenic potential of ethanol insult during the third week of human prenatal development. [source] Secondary Apoptosis of Spiral Ganglion Cells Induced by Aminoglycoside: Fas,Fas Ligand Signaling Pathway,THE LARYNGOSCOPE, Issue 9 2008Woo Yong Bae MD Abstract Objectives/Hypothesis: Hair cell loss results in the secondary loss of spiral ganglion neurons (SGNs), over a period of several weeks. The death of the SGNs themselves results from apoptosis. Previous studies have shown that several molecules are involved in the apoptosis of SGNs that occurred secondary to hair cell loss. However, the precise mechanism of apoptosis of the SGNs remains unclear. The aim of this study was to ascertain the secondary apoptosis of spiral ganglion cells induced by aminoglycoside and to investigate the role of the Fas,FasL signaling pathway using guinea pigs as an experimental animal model. Study Design: Laboratory study using experimental animals. Methods: Guinea pigs weighing 250 to 300 g (n = 21) from 3 to 4 weeks of age were used. Gentamicin (60 ,L) was injected through a cochleostomy site on their left side. At 1 (n = 7), 2 (n = 7), and 3 (n = 7) weeks after gentamicin treatment, their cochleas were obtained from their temporal bone. Hematoxylin and eosin and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling staining were performed to observe apoptosis. To investigate the involvement of the Fas,FasL signaling pathway in the secondary apoptosis of SGNs, we performed reverse transcription-polymerase chain reaction (RT-PCR), western blotting, and immunohistochemistry. Results: A progressive loss of spiral ganglion cells with increasing time after gentamicin treatment was observed on light microscopic examination. Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling staining demonstrated induction of apoptotic cell death in SGNs after gentamicin treatment. Expression of FasL increased over time after gentamicin treatment as determined by RT-PCR and western blotting. On immunohistochemical staining, we observed the localization of FasL in the SGNs. The proapoptotic molecules Bax and Bad were increased, but levels of the antiapoptotic molecule Bcl-2 were decreased at increasing survival times after gentamicin treatment on RT-PCR. The gentamicin-treated group displayed initial activation of caspase-8 and increased the cleavage of caspase-3, caspase-8, and PARP protein in a time-dependent manner. Conclusions: The secondary apoptosis of SGNs could be a result of the apoptotic Fas,FasL signaling pathway. Blocking the Fas,FasL signaling pathway could be considered as a method for preventing secondary degeneration of SGNs, and further studies are needed to confirm this. [source] Does platelet-rich plasma promote remodeling of autologous bone grafts used for augmentation of the maxillary sinus floor?CLINICAL ORAL IMPLANTS RESEARCH, Issue 3 2005Gerry M. Raghoebar Abstract: The aim of this study was to evaluate the effect of platelet-rich plasma (PRP) on remodeling of autologous bone grafts used for augmentation of the floor of the maxillary sinus. In five edentulous patients suffering from insufficient retention of their upper denture related to a severely resorbed maxilla, the floor of both maxillary sinus was augmented with an autologous bone graft from the iliac crest. Randomly, PRP was added to the bone graft used to augment the floor of the left or right sinus (split-mouth design). Three months after the reconstruction, bone biopsies were taken with a trephine from the planned implant sites (N=30). Subsequently, three implants were placed in the left and right posterior maxilla. Microradiograms were made of all biopsies (N=30), whereafter the biopsies were processed for light microscopic examination. In addition, clinical parameters were scored. Wound healing was uneventful, clinically no difference was observed between the side treated with PRP or not. Also microradiographical and histomorphological examination of the biopsies revealed no statistical difference between the PRP- and non-PRP side. One implant placed in the PRP side of the graft was lost during the healing phase. Implant-retained overdentures were fabricated 6 months after implantation. All patients functioned well (follow-up 20.2±4.3 months). In this study, no beneficial effect of PRP on wound healing and bone remodeling was observed. It is posed that PRP has no additional value in promoting healing of grafted non-critical size defects. Résumé Le but de cette étude a été d'évaluer l'effet du plasma riche en plaquettes sur le remodelage de greffons osseux autogènes utilisés pour l'épaississement du plancher sinusal. Chez cinq patients édentés souffrant d'une rétention insuffisante de leur prothèse supérieure en relation avec un maxillaire sévèrement résorbé, les planchers sinusaux des deux maxillaires ont étéépaissis avec un greffon d'os autogène provenant de la crête iliaque. Au hasard, du plasma riche en plaquettes (PRP) a été ajouté au greffon osseux utilisé pour épaissir le plancher du sinus gauche ou droit (modèle de bouche divisée). Trois mois après la reconstruction, des biopsies osseuses ont été obtenues avec un trépan des sites planifiés pour placer des implants (N=30). Ensuite, trois implants ont été placés dans les parties maxillaires gauches et droites. Des microradiogrammes des 30 biopsies ont été effectuées, ces dernières ont ensuite été utilisées pour l'examen au microscope optique. De plus, des paramètres cliniques ont été enregistrés. La guérison a été parfaite, cliniquement aucune différence n'a été observée entre les sites traités avec PRP ou sans. L'examen microradiographique et histomorphologique des biopsies n'a révélé aucune différence significative entre les sites PRP et non-PRP. Un implant placé dans le site PRP du greffon a été perdu durant la phase de guérison. Des prothèses retenues sur implants ont été fabriquées six mois après l'insertion des implants. Tous les patients ont une mise en fonction excellente après un suivi de 20±4,3 mois. Dans cette étude, aucun effet bénéfique additionnel du PRP sur la guérison et le remodelage osseux n'a été observé. Le PRP n'aurait aucune valeur supplémentaire à promouvoir la guérison dans ce type d'opération. Zusammenfassung Das Ziel dieser Studie war, den Einfluss von plättchenreichem Plasma auf die Remodellierung von autologen Knochentransplantaten, welche für die Augmentation des Sinusbodens vom Sinus maxillaris verwendet wurden, auszuwerten. Bei 5 zahnlosen Patienten, welche aufgrund einer stark resorbierten Maxilla über einen ungenügenden Halt der Oberkieferprothese klagten, wurde der Sinus maxillaris mit autologem Knochen vom Beckenkamm augmentiert. Zufällig wurde dem Knochen, der zur Augmentation des rechten oder linken Sinusbodens verwendet wurde, plättchenreiches Plasma (PRP) hinzugefügt (unterschiedlich behandelte Seiten). Drei Monate nach der Augmentation wurden mittels Hohlfräsen Biopsien an den geplanten Implantatlokalisationen entnommen (N=30). Danach wurden je drei Implantate in die rechte und linke posteriore Maxilla eingesetzt. Von allen Biopsien wurde Mikroröntgenbilder angefertigt (N=30), danach wurden die Biopsien für die lichtmikroskopische Untersuchung aufgearbeitet. Zusätzlich wurden klinische Parameter aufgenommen. Die Wundheilung war unauffällig. Klinisch konnten keine Unterschiede zwischen den mit und ohne PRP behandelten Seiten beobachtet werden. Ebenso ergab die mikroradiographische und histomorphometrische Untersuchung der Biopsien keine statistisch signifikanten zwischen der PRP und nicht-PRP Seite. Ein Implantat, welches in eine PRP Seite eingesetzt worden war, ging während der Einheilphase verloren. Die implantatgetragenen Hybridprothesen wurden 6 Monate nach Implantation angefertigt. Alle Patienten funktionierten problemlos (Beobachtungszeit bis 20.2±4.3 Monate). In dieser Studie konnte kein positiver Einfluss des PRP auf die Wundheilung und die Knochenremodellierung beobachtet werden. Es wird vermutet, dass PRP keinen zusätzlichen Effekt bei der Förderung der Heilung von Transplantaten in Defekten mit nicht-kritischer Grösse hat. Resumen La intención de este estudio fue evaluar el efecto del plasma rico en plaquetas en el remodelado de injertos de hueso autólogo usado para aumento del suelo del seno maxilar. Se aumentó el suelo de ambos senos maxilares con injertos de hueso autólogo de la cresta iliaca en 5 pacientes edéntulos que padecían de insuficiente retención de su dentadura superior relacionada con un maxilar severamente reabsorbido. Aleatoriamente, se añadió plasma rico en plaquetas (PRP) al injerto óseo usado para aumentar el suelo del seno derecho o izquierdo (diseño de boca partida). Tres meses tras la reconstrucción, se tomaron biopsias de hueso con un trépano de los lugares de implantes planificados (N=30). Subsecuentemente se colocaron tres implantes en el maxilar posterior derecho e izquierdo. Se hicieron microrradiogramas de todas las biopsias (N=30), posteriormente las biopsias se procesaron para microscopía óptica. Además se tomaron parámetros clínicos. La cicatrización de la herida tuvo lugar sin incidentes. Clínicamente no se observó diferencia alguna entre el lado tratado con PRP o no. Tampoco el examen microrradiográfico e histomorfológico de las biopsias revelaron diferencias estadísticamente significativas entre los lados con o sin PRP. Un implante colocado en el lado del PRP se perdió durante la cicatrización. Las dentaduras implantorretenidas se fabricaron a los seis meses de la implantación. Todos los pacientes funcionaron bien (seguimiento de 20.2±4.3 meses). En este estudio no se observó ningún efecto beneficioso del PRP sobre la cicatrización y sobre el remodelado óseo. Se plantea que el PRP no tiene ningún valor adicional en promover la cicatrización de defectos no críticos injertados. [source] | ||||||||||