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Superficial Layers (superficial + layer)
Selected AbstractsEqual Cosmetic Outcomes with 5-0 Poliglecaprone-25 Versus 6-0 Polypropylene for Superficial ClosuresDERMATOLOGIC SURGERY, Issue 7 2010LAURA B. ROSENZWEIG MD BACKGROUND Cutaneous sutures should provide an aesthetically pleasing result. After placing subcutaneous sutures, enough absorbable suture often remains for the superficial closure. Mohs surgeons often use a nonabsorbable suture to close the superficial layer to obtain cosmetically elegant results, but using this additional suture is less cost effective than using the remaining absorbable suture. OBJECTIVES To compare the cosmetic results of simple running sutures using an absorbable suture material (5-0 poliglecaprone-25) with those of a nonabsorbable suture (6-0 polypropylene) in primary closures of suitable facial Mohs defects. MATERIALS AND METHODS Fifty-two patients with 57 facial Mohs surgery defects appropriate for multilayer primary repair had the defects prospectively randomized into a side-by-side comparison. After closure of the deep layers with 5-0 poliglecaprone-25 sutures, half of the wound was closed with a 5-0 poliglecaprone-25 simple running suture, and the other half of the wound was closed with a 6-0 polypropylene simple running suture. The investigators blindly determined the cosmetically superior side of the closure at 1 week and 4 months after suture removal. RESULTS Forty-four patients (48 total defects) completed the study. At the 4-month follow-up, 85% (41/48) did not show any difference between poliglecaprone-25 and polypropylene, 4% (2/48) had better outcomes with poliglecaprone-25, and 10% (5/48) had better outcomes with polypropylene. There was no statistically significant cosmetic difference between the two closure types. Wound complications such as infection, hematoma, and dehiscence did not occur in any of the patients. CONCLUSION In primary closures of facial defects, using 5-0 poliglecaprone-25 or 6-0 polypropylene for the superficial closure did not affect the cosmetic result. Therefore, 5-0 poliglecaprone-25 provides a comparable and cost-effective alternative to nonabsorbable sutures for epidermal approximation in layered closures. The authors have indicated no significant interest with commercial supporters. [source] Impairment of CaMKII activation and attenuation of neuropathic pain in mice lacking NR2B phosphorylated at Tyr1472EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 5 2010Shinji Matsumura Abstract Ca2+/calmodulin-dependent protein kinase II (CaMKII) is a key mediator of long-term potentiation (LTP), which can be triggered by N -methyl- d -aspartate (NMDA) receptor-mediated Ca2+ influx. We previously demonstrated that Fyn kinase-mediated phosphorylation of NR2B subunits of NMDA receptors at Tyr1472 in the dorsal horn was involved in a neuropathic pain state even 1 week after nerve injury. Here we show that Y1472F-KI mice with a knock-in mutation of the Tyr1472 site to phenylalanine did not exhibit neuropathic pain induced by L5 spinal nerve transection, whereas they did retain normal nociceptive responses and induction of inflammatory pain. Phosphorylation of NR2B at Tyr1472 was only impaired in the spinal cord of Y1472F-KI mice among the major phosphorylation sites. There was no difference in the Ca2+ response to glutamate and sensitivity to NMDA receptor antagonists between naive wild-type and Y1472F-KI mice, and the Ca2+ response to glutamate was attenuated in the Y1472F-KI mice after nerve injury. Autophosphorylation of CaMKII at Thr286 was markedly impaired in Y1472F-KI mice after nerve injury, but there was no difference in phosphorylation of CaMKII at Thr305 or protein kinase C, at Thr674, and activation of neuronal nitric oxide synthase and microglia in the superficial layer of spinal cord between wild-type and Y1472F-KI mice after the operation. These results demonstrate that the attenuation of neuropathic pain is caused by the impaired NMDA receptor-mediated CaMKII signaling in Y1472F-KI mice, and suggest that autophosphorylation of CaMKII at Thr286 plays a central part not only in LTP, but also in persistent neuropathic pain. [source] Aberrant trajectory of thalamocortical axons associated with abnormal localization of neurocan immunoreactivity in the cerebral neocortex of reeler mutant miceEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2005Hong-Peng Li Abstract We examined the molecular mechanisms underlying the formation of the thalamocortical pathway in the cerebral neocortex of normal and reeler mutant mice. During normal development of the mouse neocortex, thalamic axons immunoreactive for the neural cell adhesion molecule L1 rarely invaded the cortical plate and ran centered in the subplate which is immunoreactive for neurocan, a brain-specific chondroitin sulfate proteoglycan. On the other hand, in homozygous reeler mutant mice, thalamic axons took an aberrant course to run obliquely through the cortical plate. Injection of bromodeoxyuridine at embryonic day 11 specifically labeled subplate neurons in normal mice, whilst in the reeler neocortex it labeled cells scattered in the cortical plate as well as in the superficial layer (superplate). Neurocan immunoreactivity was associated with the bromodeoxyuridine-positive cells in the superplate, as well as being present in oblique bands within the cortical plate, along which L1-bearing thalamic axons preferentially ran. The present results support our previous hypothesis proposed for normal rats that a heterophilic molecular interaction between L1 and neurocan is involved in determining the thalamocortical pathway within the neocortical anlage [T. Fukuda et al. (1997)Journal of Comparative Neurology, 382, 141,152]. [source] Apatite-forming ability (bioactivity) of ProRoot MTAINTERNATIONAL ENDODONTIC JOURNAL, Issue 10 2010M. G. Gandolfi Gandolfi MG, Taddei P, Tinti A, Prati C. Apatite-forming ability (bioactivity) of ProRoot MTA. International Endodontic Journal, 43, 917,929, 2010. Abstract Aim, Apatite-forming ability, considered as an index of bioactivity (bond-to-bone ability), was tested on ProRoot MTA cement after immersion in phosphate-containing solution (DPBS). Methodology, Disk samples were prepared and immersed in DPBS for 10 min, 5 h, 1 and 7 days. The cement surface was studied by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, by micro-Raman spectroscopy and by environmental scanning electron microscope with energy dispersive X-ray (ESEM-EDX) analyses. The pH of the storage solution was also investigated. Results, Spectroscopic analyses revealed calcium phosphate bands after 5-h immersion in DPBS. After 1 day, an even coating composed of apatite spherulites (0.1,0.8 micron diameter) was observed by ESEM/EDX. After 7 days, its thickness had increased. Apatite nucleation had already occurred after 5-h immersion. At this time, the presence of portlandite (i.e. Ca(OH)2, calcium hydroxide) on the cement surface was also observed; at longer times, this component was released into the medium, which underwent a remarkable pH increase. Conclusions, The study confirms the ability of ProRoot MTA to form a superficial layer of apatite within hours. The excellent bioactivity of ProRoot MTA might provide a significant clinical advantage over the traditional cements used for root-end or root-perforation repair. [source] Collagen architecture and failure processes in bovine patellar cartilageJOURNAL OF ANATOMY, Issue 4 2001JACK L. LEWIS Cartilage fails by fibrillation and wearing away. This study was designed to identify the microscopic failure processes in the collagen network of bovine cartilage using scanning electron microscopy. Cartilage samples from fibrillated cartilage from the bovine patella were removed from the bone, fixed, digested to remove proteoglycans, freeze-fractured, and processed for SEM. The architecture of the collagen network in the normal cartilage was first defined, and then the failure processes were identified by examining sites of fibrillation and at crack tips. The bovine patellar cartilage was organised with a superficial layer composed of 3,5 lamina, attached to a sub-superficial tissue by angled bridging fibrils. Collagen in the sub-superficial tissue was organised in lamina oriented in the radial direction up to the transition zone. Failure of the system occurred by cracks forming in superficial layer and lamina, creating flaps of lamina that rolled up into the larger ,fronds'. Larger cracks not following the laminar planes occurred in the transition, mid, and deep zones. Failure at the crack tips in the sub-superficial tissue appeared to be by peeling of collagen fibrils, as opposed to breaking of collagen fibrils, suggesting a ,glue' bonding the collagen fibrils in a parallel fashion. Cracks propagated by breaking these bonds. This bond could be a site of disease action, since weakening of the bond would accelerate crack propagation. [source] Structure of the skin of an air-breathing mudskipper, Periophthalmus magnuspinnatusJOURNAL OF FISH BIOLOGY, Issue 6 2002J. Y. Park The epidermis of the mudskipper Periophthalmus magnuspinnatus consisted of three layers: the outermost layer, middle layer and stratum germinativum. Extensive vascular capillary networks were present near the superficial layer of epidermis and outermost layer. The diffusion distance between the vascular capillaries and the surface of epidermis was c. 1.5 ± 0.9,m. The middle layer consisted of small or voluminous cells swollen by epidermal cells. Due to the swollen cells, the thickness of the epidermis increased and the epidermis appeared web-like. The swollen cells contained tonofilaments, lucent contents and desmosomes. Fine blood capillaries were also discernible in this layer. Well-developed lymphatic spaces containing lymphocytes existed in the stratum germinativum. Numerous blood capillaries were present under the basement membrane. The dermis consisted of a stratum laxum and stratum compactum, and there was a definite area with acid mucopolysaccharides and a small scale in the stratum laxum. The skin had an epidermal pigment cell, dendritic melanophores (-cytes) containing melanin granules within their cytoplasm, and two kinds of dermal pigment cells, melanophores and colourless pigments containing reflecting platelets. [source] Up-regulation of cerebral carbonic anhydrase by anoxic stress in pigletsJOURNAL OF NEUROCHEMISTRY, Issue 4 2003Antal Nógrádi Abstract The resuscitation of asphyxiated babies is associated with changes in cerebral protein synthesis that can influence the neurological outcome. Insufficient gas exchange results in rapid shifts in extracellular and intracellular pH. Carbonic anhydrase (CA) plays an important role in buffering acute changes in pH in the brain. We investigated whether asphyxia/re-ventilation influences the expression of cerebral CA isoforms (CA-II, CA-III and CA-IV) in anaesthetized newborn pigs. The cerebral cortex, hippocampus, cerebellum and retina were sampled, and prepared for either CA immunohistochemistry or CA immunoblotting from piglets subjected to asphyxia (10 min) followed by 2,4 h of re-ventilation, and also from normoxic controls. The CA immunoreactivity (IR) of all the isoforms studied was weak in the controls, apart from staining of a few oligodendrocytes in the subcortical white matter, some astrocytes in the superficial layer of the cerebral cortex, the cerebellar Purkinje cells and the retinal Müller cells that possessed moderate CA-II IR. However, asphyxia induced a marked increase in the CA IR of all isoforms in all the cerebral regions investigated and the retina after 4 h of survival. The pyramidal cells of the frontal cortex and hippocampus displayed the most conspicuous increase in CA IR. Immunoblotting confirmed increased levels of all the CA isoenzymes. We conclude that raised CA levels after asphyxia may contribute to the compensatory mechanisms that protect against the pathological changes in the neonatal CNS. [source] Functional properties and regional differences of human masseter motor units related to three-dimensional bite forceJOURNAL OF ORAL REHABILITATION, Issue 10 2006T. OGAWA summary, The aim of this study was to estimate numerically the properties of masseter motor units (MUs) in relation to bite force magnitude and direction three-dimensionally and to confirm the hypothesis that the properties differ between different parts of the muscle by means of simultaneous recording of MU activity along with the MU location and three-dimensional (3D) bite force. The MU activity of the right masseter of four healthy men was recorded using a monopolar needle electrode in combination with a surface reference electrode. The location of the needle electrode was estimated stereotactically with the aid of magnetic resonance images and a reference plate. The magnitude and direction of the bite force was recorded with a custom-made 3D bite force transducer. The recorded bite force was displayed on a signal processor, which enabled the participant to adjust the direction and magnitude of the force. The activities of 65 masseter MUs were recorded. Each MU had specific ranges of bite force magnitude and direction (firing range: FR) and an optimum direction for recruitment (minimum firing threshold: MFT). There was a significant negative correlation between MFT and FR width. There were functional differences in MU properties between the superficial and deep masseter and between the superficial layer and deep layer in the superficial masseter. These results indicate that the contribution of human masseter motor units to bite force production is heterogeneous within the muscle. [source] Magnetic resonance imaging and pathological findings in a case of canine idiopathic eosinophilic meningoencephalitisJOURNAL OF SMALL ANIMAL PRACTICE, Issue 8 2007C Salvadori A case of idiopathic eosinophilic meningoencephalitis in a six-month-old male Maremma shepherd dog is reported. The dog was referred with a four month history of progressive weakness and depression with loss of trained habits. Tendency to recumbency, disorientation, visual impairment, bilaterally decreased menace response and hindlimb conscious proprioception deficits were detected. Magnetic resonance imaging showed a diffuse hypointense signal involving the cerebral grey matter with enlargement of the cerebral sulci on T1-weighted and fast fluid-attenuated inversion recovery (FLAIR) sequences consistent with a diffuse necrosis or atrophy of the cortical grey matter. Histological examination revealed severe inflammatory infiltration mainly composed of eosinophils and macrophages in the subarachnoid space and in the superficial layer of the cerebral cortex where parenchymal rarefaction and necrosis of neurones were also evident. No parasites, cysts or fungi were detected, and an immunologically mediated disorder was suspected. Magnetic resonance imaging may represent a useful diagnostic tool to differentiate idiopathic eosinophilic meningoencephalitis from other inflammatory brain diseases of young dogs. [source] Plasminogen on the surfaces of fibrin clots prevents adhesion of leukocytes and plateletsJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 4 2010V. K. LISHKO Summary.,Background and Objectives: Although leukocytes and platelets adhere to fibrin with alacrity in vitro, these cells do not readily accumulate on the surfaces of fibrin clots in vivo. The difference in the capacity of blood cell integrins to adhere to fibrin in vivo and in vitro is striking and implies the existence of a physiologic antiadhesive mechanism. The surfaces of fibrin clots in the circulation are continually exposed to plasma proteins, several of which can bind fibrin and influence cell adhesion. Recently, we have demonstrated that adsorption of soluble fibrinogen on the surface of a fibrin clot results in its deposition as a soft multilayer matrix, which prevents attachment of blood cells. In the present study, we demonstrate that another plasma protein, plasminogen, which is known to accumulate in the superficial layer of fibrin, exerts an antiadhesive effect. Results: After being coated with plasminogen, the surfaces of fibrin clots became essentially non-adhesive for U937 monocytic cells, blood monocytes, and platelets. The data revealed that activation of fibrin-bound plasminogen by the plasminogen-activating system assembled on adherent cells resulted in the generation of plasmin, which decomposed the superficial fibrin layer, resulting in cell detachment under flow. The surfaces generated after the initial cell adhesion remained non-adhesive for subsequent attachment of leukocytes and platelets. Conclusion: We propose that the limited degradation of fibrin by plasmin generated by adherent cells loosens the fibers on the clot surface, producing a mechanically unstable substrate that is unable to support firm integrin-mediated cell adhesion. [source] Side-to-side linking of myocardial cells in hypertrophic cardiomyopathy: Whole heart microscopic observation with tangential sectionsPATHOLOGY INTERNATIONAL, Issue 11 2005Hirotake Masuda By cross-section or longitudinal section, it is difficult to investigate longitudinal features of myocardial cells in the whole heart. Here, introducing the use of tangential sections to obtain longitudinal aspect of myocardial cells in any part of myocardium, the authors evaluated myocardium in the left ventricle in 10 normal hearts and four hearts with hypertrophic cardiomyopathy (HCM). Tangential sections were obtained by peeling the superficial layer of myocardium. After peeling the whole surface, secondary deep layer was peeled. These procedures were repeated more than five times through the wall. Intercalated discs (ICD) were observed immunohistochemically with anti-N-cadherin and antidesmoplakin. In normal hearts, myocardial cells were cut longitudinally and ran parallel in tangential sections. They linked end-to-end with simple and regular ICD with average lengths of 120,130 µm and average sarcomere numbers of 56,65. In HCM hearts, many myocardial cells were cut almost longitudinally running approximately parallel in tangential sections. Myocardial cells frequently showed side-to-side linking characterized by skewed ICD, indistinct ICD counterparts, and longitudinally arranged ICD. Two young HCM hearts had circle-shaped ICD and vacuole-like structures highlighted by immunostaining for N-cadherin, which were actually extracellular structures comparable with irregular side-to-side linking. It is considered that side-to-side linking of myocardial cells is a characteristic microscopic feature in HCM rather than myocardial disarray. [source] Plasma-modified poly(vinyl alcohol) membranes for the dehydrationof ethanolPOLYMER INTERNATIONAL, Issue 7 2003M Rafik Abstract Non-porous poly(vinyl alcohol) (PVA) membranes prepared by a cast-evaporating technique were covered with an allyl alcohol or acrylic acid plasma-polymerized layer. The wettability and the surface energy, as well as the chemical nature of the deposit, were assigned by X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FTIR). The ability of the modified membranes for dehydrating the water/ethanol azeotropic mixture by pervaporation was studied at 25, 40 and 60 °C. The best selectivity (, = 250 at 25 °C) was obtained in the case of the allyl alcohol plasma treatment. The results obtained are discussed on the basis of the hydrophilicity as well as in terms of the weakly crosslinked superficial layer that favoured the membrane swelling. Copyright © 2003 Society of Chemical Industry [source] Development of layer-specific axonal arborizations in mouse primary somatosensory cortexTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 3 2006DeLaine D. Larsen Abstract In the developing neocortex, pyramidal neurons use molecular cues to form axonal arbors selectively in the correct layers. Despite the utility of mice for molecular and genetic studies, little work has been done on the development of layer-specific axonal arborizations of pyramidal neurons in mice. We intracellularly labeled and reconstructed the axons of layer 2/3 and layer 5 pyramidal neurons in slices of primary somatosensory cortex from C57Bl6 mice on postnatal days 7,21. For all neurons studied, the development of the axonal arborizations in mice follows a pattern similar to that seen in other species; laminar specificity of the earliest axonal branches is similar to that of mature animals. At P7, pyramidal neurons are very simple, having only a main descending axon and few primary branches. Between P7 and P10, there is a large increase in the total number of axonal branches, and axons continue to increase in complexity and total length from P10 to P21. Unlike observations in ferrets, cats, and monkeys, two types of layer 2/3 pyramidal neurons are present in both mature and developing mice; cells in superficial layer 2/3 lack axonal arbors in layer 4, and cells close to the layer 4 border have substantial axonal arbors within layer 4. We also describe axonal and dendritic arborization patterns of three pyramidal cell types in layer 5. The axons of tall-tufted layer 5 pyramidal neurons arborize almost exclusively within deep layers while tall-simple, and short layer 5 pyramidal neurons also project axons to superficial layers. J. Comp. Neurol. 494:398,414, 2006. © 2005 Wiley-Liss, Inc. [source] ORIGINAL RESEARCH,BASIC SCIENCE: Effect of Estrogen Deprivation on the Expression of Aquaporins and Nitric Oxide Synthases in Rat VaginaTHE JOURNAL OF SEXUAL MEDICINE, Issue 6 2009Sun-Ouck Kim MD ABSTRACT Introduction., The expression of aquaporin (AQP) water channels in rat vagina was recently reported. Aim., The purposes of this study were to investigate the effect of 17,-estradiol on the expression of the AQP-1 and AQP-2 water channels and nitric oxide synthase (NOS) isoforms in rat vagina. Methods., Female Sprague-Dawley rats (230,240 g, N = 90) were divided into three groups: control (N = 30), bilateral ovariectomy (N = 30), and bilateral ovariectomy, followed by subcutaneous injections of 17,-estradiol (50 µg/kg/day, N = 30). After 4 weeks, genital hemodynamics and vaginal secretions were measured after pelvic nerve stimulation, and the animals were then killed. The expression and cellular localization of AQP-1, AQP-2, endothelial NOS (e-NOS), and neuronal NOS (n-NOS) were determined in each group by immunohistochemistry and Western blot. Main Outcome Measures., The expression and cellular localization of AQPs and NOS isoforms after estrogen deprivation. Results., Estimated vaginal secretions (mg, mean ± standard error) were significantly lower in the ovariectomized group (2.9 ± 0.62) than in the control group (5.7 ± 1.25) and returned to the control value in the group after treatment with 17,-estradiol (6.5 ± 1.22) (P < 0.05). Both AQP-1 and e-NOS immunoreactivities were localized in the capillaries and venules of the lamina propria of the vagina, and n-NOS was expressed in the nerve fibers of the subepithelial lamina propria. The expression of AQP-2 was localized solely in the superficial layer of the vaginal epithelium. The protein expressions of AQP-2, e-NOS, and n-NOS were significantly lower after ovariectomy and were restored to the control level after 17,-estradiol treatment. However, there was no significant change in AQP-1 expression. Conclusions., Decreased vaginal secretion after estrogen deprivation may be partly due to functional changes in both AQPs and NOS isoforms in the vagina. The potential role of AQPs in water transport in the vagina might differ according to the type of AQP. Kim S-O, Lee H-S, Ahn K, and Park K. Effect of estrogen deprivation on the expression of aquaporins and nitric oxide synthases in rat vagina. J Sex Med 2009;6:1579,1586. [source] Epithelial differentiation of adipose-derived stem cells for laryngeal tissue engineering,THE LARYNGOSCOPE, Issue 1 2010Jennifer L. Long MD Abstract Objectives/Hypothesis: One potential treatment option for severe vocal fold scarring is to replace the vocal fold cover layer with a tissue-engineered structure containing autologous cells. As a first step toward that goal, we sought to develop a three-dimensional cell-populated matrix resembling the vocal fold layers of lamina propria and epithelium. Study Design: Basic science investigation. Methods: Adipose-derived stem cells were cultured in fibrin hydrogels with various growth factors. At the end of the culture period, matrices were sectioned and labeled with immunomarkers to identify cell phenotype. Results: Adipose-derived stem cells survived, attached, and populated three-dimensional fibrin matrices. Under select conditions, a superficial layer of cells expressing epithelial marker proteins overlay a deeper mesenchymal cell layer. Conclusions: A three-dimensional structure of fibrin and adipose-derived stem cells was created as a prototype vocal fold replacement. Two segregated cell phenotypes occurred, producing a bilayered structure resembling epithelium over lamina propria. This preliminary work demonstrates the feasibility of tissue engineering to produce structures for vocal fold replacement. Laryngoscope, 2010 [source] Homologous Collagen Substances for Vocal Fold AugmentationTHE LARYNGOSCOPE, Issue 5 2001Mark S. Courey MD Abstract Objectives/Hypothesis Dysphonia resulting from failure of glottic closure during voicing is a difficult clinical problem. Recently developed homologous collagen compounds may be beneficial in treating this problem. The objectives of this thesis are to: 1) evaluate the potential site(s) of collagen graft placement in the human vocal fold, quantify the amount of graft material that can be injected into these sites, and determine how these sites are accessed by the currently available surgical tools for injection; 2) determine the effects of the superficial vocal fold implant on laryngeal vibratory patterns and characterize how the implant affects the forces required to bring vocal folds into an adducted position for vibration; and 3) evaluate the host response to two different forms of cadaveric collagen. Study Design Prospective laboratory. Methods Three separate experiments were undertaken: 1) Eight cadaver larynges were injected with collagen compounds through a 27-gauge needle. The amount of substance required to medialize the vocal fold and potential positions for graft placement were evaluated. 2) Six cadaver larynges were mounted on a stabilizing stand while airflow, vocal fold length, adduction forces, and abduction forces on the vocal folds were manipulated. Vibratory patterns before and after the injection of the vocal folds with solubilized collagen were assessed. 3) A nude mouse model was used to study the host response to two different exogenous collagen compounds. Results Solubilized collagen compounds could be injected reliably into the superficial layer of the lamina propria (SLLP), medial portion of the thyroarytenoid muscle, or lateral portion of the thyroarytenoid muscle. When injected superficially, significantly less material was required to displace the medial edge of the vocal fold to midline (P = .0001). When graft material was placed into the medial portion of the thyroarytenoid (TA) muscle, the forces required to bring the vocal fold into a position suitable for vibration were significantly reduced (P = .0106) and the vibratory patterns of the vocal folds were not impaired. Both AlloDerm® and Dermalogen® solubilized preparations of human dermal tissue were well tolerated in the nude-mouse model. Minimal inflammatory reaction occurred. Small amounts of graft material were identified histologically at the end of the 6-month study period. The graft material appeared organized and had been infiltrated with fibroblasts of host origin. Conclusions Homologous collagen compounds can be reliably injected into the cadaveric human larynx. When the substances are injected into the medial portion of the TA muscle, immediately deep to the vocal ligament, they decrease the force of contraction needed to bring the vocal folds into a position adequate for phonation and have minimal affect on the vibratory patterns. These forms of homologous collagen are well tolerated. A small amount persists over a 6-month interval. These materials warrant further clinical trials in human subjects. [source] Comparative Histology and Vibration of the Vocal Folds: Implications for Experimental Studies in Microlaryngeal Surgery ,THE LARYNGOSCOPE, Issue 5 2000C. Gaelyn Garrett MD Abstract Objectives/Hypothesis To determine the most suitable animal model for experimental studies on vocal fold surgery and function by a histological comparison of the microflap surgical plane and laryngeal videostroboscopy (LVS) in different species of animals. A second goal was to determine how the layered vocal fold structure in humans and three different animal species affects surgical dissection within the lamina propria. Study Design Prospective laboratory. Methods Three larynges each from dogs, monkeys, and pigs were compared with three ex vivo human larynges. Microflap surgery was performed on one vocal fold from each larynx. Both the operated and nonoperated vocal folds were examined histologically using stains specific for elastin, mature collagen, and ground substance. Based on the histological results, LVS was performed on two dogs and two pigs after first performing a tracheotomy for ventilation and airflow through the glottis. Arytenoid adduction sutures were placed to facilitate vocal fold adduction. Results The distributions of the collagen and elastin fibers were found to differ among the species with concentrations varying within species. Unlike the human vocal fold, which has a higher elastin concentration in the deeper layers of the lamina propria, both the pig and the dog had a thin band of elastin concentrated just deep to the basement membrane zone in the superficial layer. Just deep to this thin band, the collagen and the elastin were less concentrated. The monkey vocal fold had a very thin mucosal layer with less elastin throughout the mucosa. The microflap dissections in each of the dog, pig, and human vocal folds were similar, being located within that portion of the superficial lamina propria where the elastin and mature collagen are less concentrated. The microflap plane in the monkey vocal fold was more deeply located near the vocalis fibers. Despite the differences in elastin concentration, the microflap plane in both the dog and the pig was found to be similar to that in humans. The dog anatomy was much more suitable for microsuspension laryngoscopy and stroboscopic examination. The dog vocal folds vibrated in a similar fashion to human vocal folds with mucosal waves and vertical phase differences, features not seen in the pig vocal folds. Conclusions Based on both the histological and stroboscopic results, the dog was believed to be a more suitable animal model for studies on vocal fold surgery, acknowledging that no animal's laryngeal anatomy is identical to that of the human. The dog LVS model presented allows for longitudinal laryngeal studies requiring repeated examinations at multiple time periods with histological correlation applied at sacrifice. [source] Expression of MicroRNA-146a in osteoarthritis cartilageARTHRITIS & RHEUMATISM, Issue 4 2009Keiichiro Yamasaki Objective A role of microRNA, which are ,22-nucleotide noncoding RNAs, has recently been recognized in human diseases. The objective of this study was to identify the expression pattern of microRNA-146a (miR-146a) in cartilage from patients with osteoarthritis (OA). Methods The expression of miR-146a in cartilage from 15 patients with OA was analyzed by quantitative reverse transcription,polymerase chain reaction (RT-PCR) and by in situ hybridization. Induction of the expression of miR-146a by cultures of normal human articular chondrocytes following stimulation with interleukin-1, (IL-1,) was examined by quantitative RT-PCR. Results All cartilage samples were divided into 3 groups according to a modification of the Mankin score (grade I = mild OA scored 0,5, grade II = moderate OA scored 6,10, and grade III = severe OA scored 11,14). In grade I OA cartilage samples, the expression of miR-146a and COL2A1 was significantly higher than that in the other groups (P < 0.05). In grades II and III OA cartilage, the expression of miR-146a and COL2A1 was decreased, whereas the expression of matrix metalloproteinase 13 (MMP-13) was elevated in grade II OA cartilage. These data showed that miR-146a is expressed intensely in cartilage with a low Mankin grade and that miR-146a expression decreases in parallel with the level of MMP-13 expression. Tissue section in situ hybridization of primary miR-146a (pri-miR-146a) revealed that pri-miR-146a was expressed in chondrocytes residing in all tissue layers, especially in the superficial layer, where it was intensely expressed. The expression of miR-146 was markedly elevated by IL-1, stimulation in human chondrocytes in vitro. Conclusion This study shows that miR-146 is intensely expressed in low-grade OA cartilage and that its expression is induced by stimulation of IL-1,. Thus, miR-146 might play a role in OA cartilage pathogenesis. [source] Increased collagen and aggrecan degradation with age in the joints of Timp3,/, miceARTHRITIS & RHEUMATISM, Issue 3 2007Solmaz Sahebjam Objective To investigate the in vivo effect of an imbalance between metalloproteinases and their inhibitors, tissue inhibitors of metalloproteinases (TIMPs), in mouse articular cartilage. Methods Hind joints of Timp3,/, and wild-type mice were examined by routine staining and by immunohistochemical analysis using antibodies specific for type X collagen and for the neoepitopes produced on proteolytic cleavage of aggrecan (, VDIPEN and , NVTEGE) and type II collagen. The neoepitope generated on cleavage of type II collagen by collagenases was quantitated in sera by enzyme-linked immunosorbent assay. Results Articular cartilage from Timp3 -knockout animals (ages ,6 months) showed reduced Safranin O staining and an increase in ,VDIPEN content compared with cartilage from heterozygous and wild-type animals. There was also a slight increase in , NVTEGE content in articular cartilage and menisci of Timp3,/, animals. Chondrocytes showed strong pericellular staining for type II collagen cleavage neoepitopes, particularly in the superficial layer, in knockout mice. Also, there was more type X collagen expression in the superficial zone of articular cartilage, especially around clusters of proliferating chondrocytes, in the knockout mice. More type II collagen cleavage product was found in the serum of Timp3,/, mice compared with wild-type animals. This increase was significant in 15-month-old animals. Conclusion These results indicate that TIMP-3 deficiency results in mild cartilage degradation similar to changes seen in patients with osteoarthritis, suggesting that an imbalance between metalloproteinases and TIMP-3 may play a pathophysiologic role in the development of this disease. [source] Keratinisation status and cytokeratins of the human Meibomian gland epitheliumACTA OPHTHALMOLOGICA, Issue 2009E KNOP Purpose The Meibomian gland (MG) is an indispensable component of the functional anatomy of the ocular surface. Increasing evidence points to a high impact of hyper-keratinisation as a major cause of obstructive MG dysfunction (MGD) and evaporative dry eye. Information of normal keratinisation status and cytokeratin composition of the human MG is limited. Methods Conjunctival whole-mount specimens including the lid margin from ten body donors of older age were embedded in paraffin. Serial sections were stained by H&E and Masson-Goldner stain and by immunohistochemistry with an antibody panel to cytokeratins. Results In conventional stains, the MG shows distinct similarities with the pilo-sebaceous unit of the cilia. The keratinised skin epithelium extended into the terminal part of the MG excretory duct similar to the hair follicle. Preliminary IHC results showed that the epithelium was positive there for the skin keratin CK10. Along the central duct the keratinisation CK10 expression was gradually lost similar to keratinisation marker involucrin. However, filaggrin, a marker for incipient stages of keratinisation and located in keratohyalin granules continued in the superficial layer of the duct epithelium all along the Meibomian central ductal system. CK14 a marker for basal undifferentiated cells showed a homogenous expression all along the basal cell layer of the MG ducts and the acini. Conclusion The MG shares similarities with the cilia in embryology, in structure and in the cytokeratin composition. It can hence be regarded as a "hair without a hair shaft". All parts of the MG ducts have signs of incipient keratinisation and preserve a commitment to keratinisation. Upregulation in MGD explain hyper-keratinisation as a typical event in obstructive MGD. [source] Glutamine induces epileptiform discharges in superficial layers of the medial entorhinal cortex from pilocarpine-treated chronic epileptic rats in vitroEPILEPSIA, Issue 4 2009Nora Sandow Summary Purpose:, Glutamine (GLN) is a precursor for synthesis of glutamate and ,-aminobutyric acid (GABA) and has been found in the cerebrospinal fluid (CSF) at mean concentrations of 0.6 mM. Experiments on slices are usually performed in artificial CSF (aCSF) kept free of amino acids. Therefore, the role of glutamine, particularly in tissue of epileptic animals, remains elusive. Methods:, Using extracellular recordings we studied effects of GLN on field potentials and stimulus-evoked field responses in the medial entorhinal cortex (MEC) of combined entorhinal cortex hippocampal slices from pilocarpine-treated chronic epileptic rats and age-matched saline-injected control rats. Results:, In presence of GLN (0.5 and 2 mM) recurrent epileptiform discharges (REDs) were observed in slices from epileptic rats (64% and 80%, respectively), but not in slices from control rats. REDs were restricted to the superficial MEC, suppressed by the ,-Amino-3-hydroxy-5-methyl-4-isoxazol-propionate (AMPA)/kainate receptor antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (30 ,M), attenuated by the inhibitor of neuronal glutamine transporters methylamino-isobutyric acid (10 mM), and apparently augmented and prolonged by the GABAA receptor antagonist bicuculline-methiodide (5 ,M). In contrast, amplitudes of stimulus evoked nonsynaptic and synaptic field responses increased in slices from control rats (+23% and +12% of the reference values) and insignificantly less or not in those of epileptic rats (+6.5% and ,0.25%, respectively). Notably, stimulus-evoked slow negative transients confined to slices of epileptic animals were reduced in amplitude (,18%). Discussion:, In combined entorhinal hippocampal slices from chronic epileptic animals, GLN induces glutamatergic REDs via neuronal uptake in superficial layers of the MEC where inhibitory function seemed to be partially preserved. [source] Topographic distribution of direct and hippocampus- mediated entorhinal cortex activity evoked by olfactory tract stimulationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2004Vadym Gnatkovsky Abstract Olfactory information is central for memory-related functions, such as recognition and spatial orientation. To understand the role of olfaction in learning and memory, the distribution and propagation of olfactory tract-driven activity in the parahippocampal region needs to be characterized. We recently demonstrated that repetitive stimulation of the olfactory tract in the isolated guinea pig brain preparation induces an early direct activation of the rostrolateral entorhinal region followed by a delayed response in the medial entorhinal cortex (EC), preceded by the interposed activation of the hippocampus. In the present study we performed a detailed topographic analysis of both the early and the delayed entorhinal responses induced by patterned stimulation of the lateral olfactory tract in the isolated guinea pig brain. Bi-dimensional maps of EC activity recorded at 128 recording sites with 4 × 4 matrix electrodes (410 µm interlead separation) sequentially placed in eight different positions, showed (i) an early (onset at 16.09 ± 1.2 ms) low amplitude potential mediated by the monosynaptic LOT input, followed by (ii) an associative potential in the rostral EC which originates from the piriform cortex (onset at 33.2 ± 2.3 ms), and (iii) a delayed potential dependent on the previous activation of the hippocampus. The sharp component of the delayed response had an onset latency between 52 and 63 ms and was followed by a slow wave. Laminar profile analysis demonstrated that in the caudomedial EC the delayed response was associated with two distinct current sinks located in deep and in superficial layers, whereas in the rostrolateral EC a small-amplitude sink could be detected in the superficial layers exclusively. The present report demonstrates that the output generated by the hippocampal activation is unevenly distributed across different EC subregions and indicates that exclusively the medial and caudal divisions receive a deep-layer input from the hippocampus. In the rostrolateral EC, specific network interactions may be generated by the convergence of the direct olfactory input and the olfaction-driven hippocampal output. [source] Electrophysiological characterization of interlaminar entorhinal connections: an essential link for re-entrance in the hippocampal,entorhinal systemEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2003Fabian Kloosterman Abstract The hippocampal formation communicates with the neocortex mainly through the adjacent entorhinal cortex. Neurons projecting to the hippocampal formation are found in the superficial layers of the entorhinal cortex and are largely segregated from the neurons receiving hippocampal output, which are located in deep entorhinal layers. We studied the communication between deep and superficial entorhinal layers in the anaesthetized rat using field potential recordings, current source density analysis and single unit measurements. We found that subiculum stimulation was able to excite entorhinal neurons in deep layers. This response was followed by current sinks in superficial layers. Both responses were subject to frequency dependent facilitation, but not depression. Selective blockade of deep layer responses also abolished subsequent superficial layer responses. This clearly demonstrates a functional deep-to-superficial layer communication in the entorhinal cortex, which can be triggered by hippocampal output. This pathway may provide a means by which processed hippocampal output is integrated or compared with new incoming information in superficial entorhinal layers, and it constitutes an important link in the process of re-entrance of activity in the hippocampal,entorhinal network, which may be important for consolidation of memories or retaining information for short periods. [source] Peripheral axotomy induces only very limited sprouting of coarse myelinated afferents into inner lamina II of rat spinal cordEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2002Lan Bao Abstract Peripheral axotomy-induced sprouting of thick myelinated afferents (A-fibers) from laminae III,IV into laminae I,II of the spinal cord is a well-established hypothesis for the structural basis of neuropathic pain. However, we show here that the cholera toxin B subunit (CTB), a neuronal tracer used to demonstrate the sprouting of A-fibers in several earlier studies, also labels unmyelinated afferents (C-fibers) in lamina II and thin myelinated afferents in lamina I, when applied after peripheral nerve transection. The lamina II afferents also contained vasoactive intestinal polypeptide and galanin, two neuropeptides mainly expressed in small dorsal root ganglion (DRG) neurons and C-fibers. In an attempt to label large DRG neurons and A-fibers selectively, CTB was applied four days before axotomy (pre-injury-labelling), and sprouting was monitored after axotomy. We found that only a small number of A-fibers sprouted into inner lamina II, a region normally innervated by C-fibers, but not into outer lamina II or lamina I. Such sprouts made synaptic contact with dendrites in inner lamina II. Neuropeptide Y (NPY) was found in these sprouts in inner lamina II, an area very rich in Y1 receptor-positive processes. These results suggest that axotomy-induced sprouting from deeper to superficial layers is much less pronounced than previously assumed, in fact it is only marginal. This limited reorganization involves large NPY immunoreactive DRG neurons sprouting into the Y1 receptor-rich inner lamina II. Even if quantitatively small, it cannot be excluded that this represents a functional circuitry involved in neuropathic pain. [source] Topographical projection from the superior colliculus to the nucleus of the brachium of the inferior colliculus in the ferret: convergence of visual and auditory informationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2000Timothy P. Doubell Abstract The normal maturation of the auditory space map in the deeper layers of the ferret superior colliculus (SC) depends on signals provided by the superficial visual layers, but it is unknown where or how these signals influence the developing auditory responses. Here we report that tracer injections in the superficial layers label axons with en passant and terminal boutons, both in the deeper layers of the SC and in their primary source of auditory input, the nucleus of the brachium of the inferior colliculus (nBIC). Electron microscopy confirmed that biocytin-labelled SC axons form axodendritic synapses on nBIC neurons. Injections of biotinylated dextran amine in the nBIC resulted in anterograde labelling in the deeper layers of the SC, as well as retrogradely labelled superficial and deep SC neurons, whose distribution varied systematically with the rostrocaudal placement of the injection sites in the nBIC. Topographical order in the projection from the SC to the ipsilateral nBIC was confirmed using fluorescent microspheres. We demonstrated the existence of functional SC-nBIC connections by making whole-cell current-clamp recordings from young ferret slices. Both monosynaptic and polysynaptic EPSPs were generated by electrical stimulation of either the superficial or deep SC layers. In addition to unimodal auditory units, both visual and bimodal visual,auditory units were recorded in the nBIC in vivo and their incidence was higher in juvenile ferrets than in adults. The SC-nBIC circuit provides a potential means by which visual and other sensory or premotor signals may be delivered to the nBIC to calibrate the representation of auditory space. [source] Orthogonal polarization technique in the assessment of human skin microcirculationINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 5 2008Omar Lupi MD Background The "gold standard" for the study of the in vivo microcirculation is intravital microscopy. The recently developed method of orthogonal polarization of light [orthogonal polarization spectral (OPS) imaging] allows for the in vivo transcutaneous evaluation of the microcirculation without the need for invasive surgical procedures. Methods The application of polarized light originating from a 100 W halogen tungsten lamp is able to penetrate tissues at a depth of up to 3 mm, and generates reissued light from this depth. The evaluation of this depolarized light, from a deeper origin, may be carried out separately from the light reflected by the more superficial layers of the tissue under study because this light retains photon polarization, whereas the former light undergoes real depolarization. Results The process of validation of the OPS technique, when compared with intravital microscopy, the "gold standard" for the in vivo observation of the microcirculation, has shown that it is as effective and reliable as the gold standard, reaching the same resolution level in the visualization of blood vessels, but without the need for invasive surgical procedures. Conclusions The OPS technique is a very promising tool for dermatologists and researchers, especially in the study of vasculitis, chronic venous insufficiency, and skin tumors. [source] Topographical and laminar distribution of cortical input to the monkey entorhinal cortexJOURNAL OF ANATOMY, Issue 2 2007A. Mohedano-Moriano Abstract Hippocampal formation plays a prominent role in episodic memory formation and consolidation. It is likely that episodic memory representations are constructed from cortical information that is mostly funnelled through the entorhinal cortex to the hippocampus. The entorhinal cortex returns processed information to the neocortex. Retrograde tracing studies have shown that neocortical afferents to the entorhinal cortex originate almost exclusively in polymodal association cortical areas. However, the use of retrograde studies does not address the question of the laminar and topographical distribution of cortical projections within the entorhinal cortex. We examined material from 60 Macaca fascicularis monkeys in which cortical deposits of either 3H-amino acids or biotinylated dextran-amine as anterograde tracers were made into different cortical areas (the frontal, cingulate, temporal and parietal cortices). The various cortical inputs to the entorhinal cortex present a heterogeneous topographical distribution. Some projections terminate throughout the entorhinal cortex (afferents from medial area 13 and posterior parahippocampal cortex), while others have more limited termination, with emphasis either rostrally (lateral orbitofrontal cortex, agranular insular cortex, anterior cingulate cortex, perirhinal cortex, unimodal visual association cortex), intermediate (upper bank of the superior temporal sulcus, unimodal auditory association cortex) or caudally (parietal and retrosplenial cortices). Many of these inputs overlap, particularly within the rostrolateral portion of the entorhinal cortex. Some projections were directed mainly to superficial layers (I,III) while others were heavier to deep layers (V,VI) although areas of dense projections typically spanned all layers. A primary report will provide a detailed analysis of the regional and laminar organization of these projections. Here we provide a general overview of these projections in relation to the known neuroanatomy of the entorhinal cortex. [source] Decreased density of muscarinic receptors in the superior temporal gyrusin schizophreniaJOURNAL OF NEUROSCIENCE RESEARCH, Issue 6 2005Chao Deng Abstract Recent studies have indicated that muscarinic receptors are involved in the pathophysiology in schizophrenia, particularly in cognitive deficits. The superior temporal gyrus (STG) is an area that has also been strongly implicated in the pathophysiology of schizophrenia. Therefore, in this study, we investigated the binding density of two muscarinic antagonists, [3H]pirenzepine and [3H]AF-DX384, in the STG of schizophrenia patients compared with controls. A significant decrease (44% in the superficial layers and 48% in the deep layers, P < 0.01) in binding density of [3H]pirenzepine was observed in schizophrenia patients, which suggested a reduction of muscarinic M1 and M4 receptor densities in the STG of schizophrenia patients. A tendency toward decreased [3H]AF-DX384 binding density (34%, P = 0.09) was also observed in schizophrenia patients compared with controls. Because of the positive correlation between [3H]pirenzepine and [3H]AF-DX384 binding, and, insofar as both ligands have high affinities for the M4 receptor, the involvement of M4 receptor alteration is also suggested in the STG in schizophrenia. These results suggest that changes of the muscarinic receptors M1 and M4 might contribute to the STG pathology in schizophrenia. © 2005 Wiley-Liss, Inc. [source] Proliferation and differentation markers in snuff-induced oral mucosal lesionsJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 5 2002Marina Merne Abstract Background: Regular use of snuff is known to cause whitish oral mucosal lesions of variable severity at the usual quid placement site. The main aim of this study was to elucidate cellular mechanisms involved in snuff-induced epithelial changes. Methods: Expression patterns for markers of cell proliferation (PCNA, Ki-67), cell cycle regulation (p53, p21), keratin changes (pankeratin, CK18, CK19), cell stress (HSP 70) and collagen type IV in 14 snuff-induced oral mucosal lesions and 12 control samples were analyzed by immunohistochemistry (IHC). Results: On light microscopy, all snuff-induced lesions were characterized by a hyperkeratinized and thickened epithelium. Some vacuolized cells, markers of cell degeneration, were frequently seen (in 9/14 of the samples) in the superficial layers in epithelia. Expression of PCNA and Ki-67 was found in a statistically significantly fewer cells in snuff-induced lesions (P < 0.001) than in the controls. This indicates that epithelia in snuff-induced lesions are not thickened as a result of increased cellular proliferation, but by protracted turnover of differentiating cells. Of cell cycle markers, p21 was found be up-regulated in 4/14 snuff-induced lesions, probably by p53-independent pathways. Only two snuff-induced lesions showed p53 positivity. However, the number of stained cells with p53 and p21 was not statistically different from that in controls. Expression of CK18, but not any alterations in CK19 expression, was seen in 5 of 14 snuff-induced lesions. Snuff also seems to stimulate the expression of collagen type IV, possibly by basal cells, as indicated by the thickened staining of the basal lamina. Conclusions: The findings of this study showing suppressed cellular proliferation and infrequent p53 dysfunction in snuff lesions may partly explain why dysplastic changes are seldom seen in mucosal lesions induced by the Scandinavian type of snuff. [source] Expression pattern of adhesion molecules in junctional epithelium differs from that in other gingival epitheliaJOURNAL OF PERIODONTAL RESEARCH, Issue 4 2006S. Hatakeyama Background and Objective:, The gingival epithelium is the physiologically important interface between the bacterially colonized gingival sulcus and periodontal soft and mineralized connective tissues, requiring protection from exposure to bacteria and their products. However, of the three epithelia comprising the gingival epithelium, the junctional epithelium has much wider intercellular spaces than the sulcular epithelium and oral gingival epithelium. Hence, the aim of the present study was to characterize the cell adhesion structure in the junctional epithelium compared with the other two epithelia. Material and Methods:, Gingival epithelia excised at therapeutic flap surgery from patients with periodontitis were examined for expression of adhesion molecules by immunofluorescence. Results:, In the oral gingival epithelium and sulcular epithelium, but not in the junctional epithelium, desmoglein 1 and 2 in cell,cell contact sites were more abundant in the upper than the suprabasal layers. E-cadherin, the main transmembranous molecule of adherens junctions, was present in spinous layers of the oral gingival epithelium and sulcular epithelium, but was scarce in the junctional epithelium. In contrast, desmoglein 3 and P-cadherin were present in all layers of the junctional epithelium as well as the oral gingival epithelium and sulcular epithelium. Connexin 43 was clearly localized to spinous layers of the oral gingival epithelium, sulcular epithelium and parts of the junctional epithelium. Claudin-1 and occludin were expressed in the cell membranes of a few superficial layers of the oral gingival epithelium. Conclusion:, These findings indicated that the junctional epithelium contains only a few desmosomes, composed of only desmoglein 3; adherens junctions are probably absent because of defective E-cadherin. Thus, the anchoring junctions connecting junctional epithelium cells are lax, causing widened intercellular spaces. In contrast, the oral gingival epithelium, which has a few tight junctions, functions as a barrier. [source] | ||||||||||||||||