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Histological Analysis (histological + analysis)
Selected AbstractsCharacterization of the cardiac phenotype in neonatal Ts65Dn miceDEVELOPMENTAL DYNAMICS, Issue 2 2008Austin D. Williams Abstract The Ts65Dn mouse is the most-studied of murine models for Down syndrome. Homology between the triplicated murine genes and those on human chromosome 21 correlates with shared anomalies of Ts65Dn mice and Down syndrome patients, including congenital heart defects. Lethality is associated with inheritance of the T65Dn chromosome, and anomalies such as right aortic arch with Kommerell's diverticulum and interrupted aortic arch were found in trisomic neonates. The incidence of gross vascular abnormalities was 17% in the trisomic population. Histological analyses revealed interventricular septal defects and broad foramen ovale, while immunohistochemistry showed abnormal muscle composition in the cardiac valves of trisomic neonates. These findings confirm that the gene imbalance present in Ts65Dn disrupts crucial pathways during cardiac development. The candidate genes for congenital heart defects that are among the 104 triplicated genes in Ts65Dn mice are, therefore, implicated in the dysregulation of normal cardiogenic pathways in this model. Developmental Dynamics 237:426,435, 2008. © 2007 Wiley-Liss, Inc. [source] Transplantation of galectin-1-expressing human neural stem cells into the injured spinal cord of adult common marmosetsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2010Junichi Yamane Abstract Delayed transplantation of neural stem/progenitor cells (NS/PCs) into the injured spinal cord can promote functional recovery in adult rats and monkeys. To enhance the functional recovery after NS/PC transplantation, we focused on galectin-1, a carbohydrate-binding protein with pleiotropic roles in cell growth, differentiation, apoptosis, and neurite outgrowth. Here, to determine the combined therapeutic effect of NS/PC transplantation and galectin-1 on spinal cord injury (SCI), human NS/PCs were transfected by lentivirus with galectin-1 and green fluorescent protein (GFP), (Gal-NS/PCs) or GFP alone (GFP-NS/PCs), expanded in vitro, and then transplanted into the spinal cord of adult common marmosets, 9 days after contusive cervical SCI. The animals' motor function was evaluated by their spontaneous motor activity, bar grip power, and performance on a treadmill test. Histological analyses revealed that the grafted human NS/PCs survived and differentiated into neurons, astrocytes, and oligodendrocytes. There were significant differences in the myelinated area, corticospinal fibers, and serotonergic fibers among the Gal-NS/PC, GFP-NS/PC, vehicle-control, and sham-operated groups. The Gal-NS/PC-grafted animals showed a better performance on all the behavioral tests compared with the other groups. These findings suggest that Gal-NS/PCs have better therapeutic potential than NS/PCs for SCI in nonhuman primates and that human Gal-NS/PC transplantation might be a feasible treatment for human SCI. © 2010 Wiley-Liss, Inc. [source] Early therapeutic intervention in females with Fabry disease?ACTA PAEDIATRICA, Issue 2008Derralynn A Hughes Abstract Anderson,Fabry disease is an X-linked lysosomal storage disorder resulting from deficiency of ,-galactosidase A. The subsequent accumulation of globotriaosylceramide (Gb3) in cells and tissues of the body has multisystemic effects and significantly impacts upon quality of life and survival of individuals with this condition. In general, Anderson,Fabry disease is more severe in male patients; however, despite X-linkage, females may develop severe signs and symptoms of the disease, although there is considerable phenotypic heterogeneity, which correlates most closely with age. Histological analyses of biopsies have shown evidence of Gb3 storage in the kidney and heart in female patients. Gb3 levels are also elevated in the urine of females, although plasma Gb3 levels are not reliably elevated. The efficacy of enzyme replacement therapy (ERT) with recombinant human ,-galactosidase A has been demonstrated in females in a clinical trial and in observational studies, including those using data from outcome surveys. Benefits include a reduction in left ventricular mass, stabilization of renal function and improvements in pain and quality of life. Conclusion: If early intervention with ERT in females is to be advocated, it is necessary to demonstrate not only that females with Anderson,Fabry disease have clinical and biochemical features of ,-galactosidase A deficiency and respond to ERT, but also that early intervention prevents the onset of the later manifestations of the disorder. Any strategy for early therapy should also balance future advantages against any impact on quality of life. [source] Telangiectatic adenoma: An entity associated with increased body mass index and inflammation,HEPATOLOGY, Issue 1 2007Valérie Paradis What were previously called telangiectatic focal nodular hyperplasias are in fact true adenomas with telangiectatic features (TAs) without overt characterized genetic abnormalities. The aim of our study was to review a surgical series of TAs in order to describe clinical, biological, and radiological findings of these lesions and to evaluate their outcomes. From January 1996 to November 2005, 284 patients with benign hepatocellular nodules underwent surgical resection at Beaujon Hospital. Among them, 32 TAs from 27 patients were diagnosed. Ninety-two percent of the patients were women. Mean age was 38 years (range 17,63). Mean body mass index was 28 (range 18,49), with 16 patients being overweight. Symptoms revealed lesions in 10 patients. In 13 patients, TA was associated with another benign liver lesion. Mean size of the TAs was 5 cm (range 1,17 cm). Histological analysis showed cellular atypias in 6 cases (19%), steatosis in 17 cases (53%), vascular changes in 19 cases (59%), and significant inflammatory infiltrate in 29 cases (91%). In 1 case, the TA had foci of well-differentiated hepatocellular carcinoma. In 18 of the 26 cases (69%), adjacent liver showed significant steatosis. Serum biomarkers of inflammation were increased in 90% of patients (19 of 22). After surgical resection, inflammatory marker levels returned to normal values in all patients tested. Conclusion: This study has shown that TAs occur in a characteristic background of overweight patients and are often associated with a biological inflammatory syndrome. Moreover, a TA may progress to malignancy. (HEPATOLOGY 2007;46:140,146.) [source] Protection against Fas-induced liver apoptosis in transgenic mice expressing cyclooxygenase 2 in hepatocytes,HEPATOLOGY, Issue 3 2007Marta Casado Cyclooxygenase-2 (COX-2) is upregulated in many cancers, and the prostanoids synthesized increase proliferation, improve angiogenesis, and inhibit apoptosis in several tissues. To explore the function of COX-2 in liver, transgenic (Tg) mice were generated containing a fusion gene (LIVhCOX-2) consisting of human COX-2 cDNA under the control of the human ApoE promoter. Six lines were developed; all of them expressed the LIVhCOX-2 transgene selectively in hepatocytes. The Tg mice exhibited a normal phenotype, and the increased levels of PGE2 found were due to the constitutively expressed COX-2. Histological analysis of different tissues and macroscopic examination of the liver showed no differences between wild-type (Wt) and Tg animals. However, Tg animals were resistant to Fas-mediated liver injury, as demonstrated by low levels of plasmatic aminotransferases, a lesser caspase-3 activation, and Bax levels and an increase in Bcl-2, Mcl-1, and xIAP proteins, when compared with the Wt animals. Moreover, the resistance to Fas-mediated apoptosis is suppressed in the presence of COX-2,selective inhibitors, which prevented prostaglandin accumulation in the liver of Tg mice. Conclusion: These results demonstrate that expression of COX-2,dependent prostaglandins exerted a protection against liver apoptosis. (HEPATOLOGY 2007;45:631,638.) [source] Anti-interleukin-6 monoclonal antibody inhibits autoimmune responses in a murine model of systemic lupus erythematosusIMMUNOLOGY, Issue 3 2006Bailin Liang Summary Systemic lupus erythematosus (SLE) is an autoimmune disease resulting from dysregulation of the immune system. Interleukin-6 (IL-6) is a multifunctional cytokine produced by macrophages, monocytes and T and B cells. It stimulates B-cell differentiation/maturation, immunoglobulin secretion, and T-cell functions. Elevated levels of IL-6 in serum, urine and renal glomeruli were detected in patients with active SLE and in murine models of SLE. Our study investigated the role of IL-6 in an SLE-like disease in New Zealand Black/White (NZB/W) F1 mice by administration of an anti-murine IL-6 monoclonal antibody (mAb). Intraperitoneal administration of the anti-IL-6 mAb suppressed the production of anti-dsDNA autoantibody. B-cell proliferation induced by anti-IgM and anti-CD40 was lower in the anti-IL-6 mAb-treated mice, ex vivo studies demonstrated that anti-IL-6 mAb treatment inhibited anti-dsDNA production. Anti-CD3-induced T-cell proliferation and mixed lymphocyte reactions were inhibited by anti-IL-6 mAb treatment, indicating a partial down-regulation of T cells. Histological analysis showed that treatment with anti-IL-6 mAb prevented the development of severe kidney disease. These results suggest that treatment with anti-IL-6 mAb has a beneficial effect on autoimmunity in murine SLE and that autoreactive B cells may be the primary target for anti-IL-6 mAb treatment; its effect on autoreactive T cells is also indicated. [source] An ex vivo swine tracheal organ culture for the study of influenza infectionINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 1 2010Sandro F. Nunes Background The threat posed by swine influenza viruses with potential to transmit from pig populations to other hosts, including humans, requires the development of new experimental systems to study different aspects of influenza infection. Ex vivo organ culture (EVOC) systems have been successfully used in the study of both human and animal respiratory pathogens. Objectives We aimed to develop an air interface EVOC using pig tracheas in the study of influenza infection demonstrating that tracheal explants can be effectively maintained in organ culture and support productive influenza infection. Methods Tracheal explants were maintained in the air interface EVOC system for 7 days. Histological characteristics were analysed with different staining protocols and co-ordinated ciliary movement on the epithelial surface was evaluated through a bead clearance assay. Explants were infected with a swine H1N1 influenza virus. Influenza infection of epithelial cells was confirmed by immunohistochemistry and viral replication was quantified by plaque assays and real-time RT-PCR. Results Histological analysis and bead clearance assay showed that the tissue architecture of the explants was maintained for up to 7 days, while ciliary movement exhibited a gradual decrease after 4 days. Challenge with swine H1N1 influenza virus showed that the EVOC tracheal system shows histological changes consistent with in vivo influenza infection and supported productive viral replication over multiple cycles of infection. Conclusion The air interface EVOC system using pig trachea described here constitutes a useful biological tool with a wide range of applications in the study of influenza infection. [source] Acquired localized cutis laxa confined to the face: case report and review of the literatureINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 12 2004Claudia Jimena Perafán Riveros MD Background, Cutis laxa is an uncommon entity characterized by laxity of the skin, which hangs in loose folds, producing the appearance of premature aging. It can be subdivided into congenital and acquired. This latter variant is rare and the skin involvement varies from generalized to localized. We report a case of a localized acquired cutis laxa confined to the face, without preceding inflammatory lesions or systemic compromise. Four similar cases have been reported to date. The etiology remains unknown and there is no definitive treatment. Methods, A 27-year-old White woman came to our hospital with a wrinkled face, pendulous earlobes and drop eyelids. Changes began 5 years prior, and she appeared much older than her age. Results, Histological analysis and ultrastructural examination of skin biopsy revealed reduction and fragmentation of elastic fibers, confirming the diagnosis of cutis laxa. No systemic involvement was diagnosed. The patient was submitted to plastic surgery for repair, with satisfactory results to date. Conclusions, Acquired localized cutis laxa confined to the face without preceding inflammatory lesions is extremely rare. The etiology remains unknown. Clinical features and histopathologic findings confirm the diagnosis. Surgical repair seems to be the only therapeutic choice, but the results are variable and temporary. [source] Effect of the antimicrobial peptide indolicidin on the green peach aphid Myzus persicae (Sulzer)JOURNAL OF APPLIED ENTOMOLOGY, Issue 2 2007R. R. Le-Feuvre Abstract:, The green-peach aphid, Myzus persicae (Sulzer) (Hem., Aphididae), is a major agricultural pest of a wide range of host plants, causing damage by feeding and indirectly by transmitting viruses. In this study we tested the effect of the antimicrobial peptide indolicidin on M. persicae survival and on its essential bacterial endosymbionts. Artificial diet bioassays showed a significant dose-dependent lethal response of indolicidin on M. persicae survival (LD50 of 209 ± 60 ,g/ml). Histological analysis of indolicidin-treated aphids revealed a lower number of distorted mycetocytes, whereas control aphids showed abundant number of rounded and filled mycetocytes. These results suggest that aphid survival could be affected via reduction of its endosymbionts. Thus, aphid control based on antimicrobial substances against endosymbionts could be a promising strategy that needs to be further explored. [source] A biomechanical and histological analysis of standard versus hydroxyapatite-coated pins for external fixationJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2008Antonio Moroni Abstract This sheep study was designed to make a comparative evaluation of two external fixation pin types each with and without hydroxyapatite (HA) coating. The two pins had different taper, pitch, and self drilling capabilities. Twenty Orthofix standard, self-tapping pins (group A), 20 Orthofix HA-coated, self-tapping pins (group B), 20 X-caliber, self-drilling, self-tapping pins (group C), and 20 X-caliber HA-coated, self-drilling, self-tapping pins (group D) were selected. Four pins were implanted in the right femurs of 20 adult sheep that were euthanized at 6 weeks. Mean pin insertion torque was 2745 ± 822 Nmm in group A, 2726 ± 784 Nmm in group B, 2818 ± 552 Nmm in group C, and 2657 ± 732 Nmm in group D (ns). Mean pin extraction torque was 1567 ± 541 Nmm in group A, 2524 ± 838 Nmm in group B, 1650 ± 650 Nmm in group C, and 2517 ± 726 Nmm in group D. HA-coated pins (group B and D) had a significantly greater mean pin extraction torque compared to similar uncoated pins (group A and C) (p < 0.0005). Histological analysis showed good osteointegration of the two coated pin types. This study shows that HA-coating is more important for optimal pin fixation than the particular combination of design parameters used in each pin type. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008 [source] In vivo evaluation of hydroxyapatite foamsJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 4 2002P. Sepulveda Abstract Hydroxyapatite (HA) is widely applied as bone graft material due to its osteoconductive potential and well-established biocompatibility. In this work, macroporous hydroxyapatite structures made through foaming of aqueous suspensions and gelcasting were tested for in vivo osteointegration. These foams are composed of a three-dimensional array of spherical pores with diameters of approximately 100,500 ,m, interconnected by windows of smaller size in the range of 30,120 ,m. The HA foams were implanted in the tibia of albino New Zealand rabbits and removed after a period of 8 weeks. Histological analysis revealed that the pores in the foams were partially or completely filled progressively with mature new bone tissue and osteoid after the implanted period. No immune or inflammatory reactions were detected. The high osteoconductive potential of the HA foams provides a potential structure for use as bone substitute in orthopedic, oral, and cranio-maxillofacial reconstructive surgery, and as dento-alveolar implants. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 587,592, 2002 [source] Noggin Inhibits Postoperative Resynostosis in Craniosynostotic Rabbits,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2007Gregory M Cooper PhD Abstract Inhibition of bone formation after surgery to correct craniosynostosis would alleviate the need for secondary surgeries and decrease morbidity and mortality. This study used a single dose of Noggin protein to prevent resynostosis and improve postoperative outcomes in a rabbit model of craniosynostosis. Introduction: Craniosynostosis is defined as the premature fusion of one or more of the cranial sutures, which causes secondary deformations of the cranial vault, cranial base, and brain. Current surgical intervention involves extirpation of the fused suture to allow unrestricted brain growth. However, resynostosis of the extirpated regions often occurs. Several bone morphogenetic proteins (BMPs), well-described inducers of ossification, are involved in bone healing. This study tested the hypothesis that a postoperative treatment with Noggin, an extracellular BMP inhibitor, can inhibit resynostosis in a rabbit model of human familial nonsyndromic craniosynostosis. Materials and Methods: Thirty-one New Zealand white rabbits with bilateral coronal suture synostosis were divided into three groups: (1) suturectomy controls (n = 13); (2) suturectomy with BSA in a slow-resorbing collagen vehicle, (n = 8); and (3) suturectomy with Noggin in a slow-resorbing collagen vehicle (n = 10). At 10 days of age, a 3 × 15-mm coronal suturectomy was performed. The sites in groups 2 and 3 were immediately filled with BSA-loaded gel or Noggin-loaded gel, respectively. Serial 3D-CT scan reconstructions of the defects and standard radiographs were obtained at 10, 25, 42, and 84 days of age, and the sutures were harvested for histological analysis. Results: Radiographic analysis revealed that Noggin-treated animals had significantly greater coronal suture marker separation by 25 days and significantly greater craniofacial length at 84 days of age compared with controls. 3D-CT analysis revealed that Noggin treatment led to significantly greater defect areas through 84 days and to increased intracranial volumes at 84 days of age compared with other groups. Histological analysis supported CT data, showing that the untreated and BSA-treated groups had significant healing of the suturectomy site, whereas the Noggin-treated group had incomplete wound healing. Conclusions: These data support our hypothesis that inhibition of BMP activity using Noggin may prevent postoperative resynostosis in this rabbit model. These findings also suggest that Noggin therapy may have potential clinical use to prevent postoperative resynostosis in infants with craniosynostosis. [source] Gorham-Stout Disease,Stabilization During Bisphosphonate Treatment,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 2 2005Fabian Hammer Abstract A 45-year-old woman presented with recent onset of left-sided chest pain. On clinical examination, these symptoms seemed to be strictly localized to a region that was marked by a long-standing cutaneous erythematous lesion. Laboratory results showed no gross abnormalities. Radiological imaging including conventional X-ray, MRI scans, and 3D CT reconstruction of the rib cage revealed circumscript destruction of the left lateral ribs 9,11. Histological analysis of a rib biopsy showed angiomatous hypervascularization and intracortical fibrosis. In keeping with these findings, the patient's condition was diagnosed as Gorham-Stout disease, a rare condition with localized, often unilateral, bone destruction. Monotherapy with bisphosphonates (pamidronate 30 mg IV every 3 months) was initiated, leading to rapid disappearance of local pain. Follow-up over 24 months documented a stable clinical and radiological picture without evidence of progressive bone destruction. [source] Chondrosarcoma in Association With Primary Hyperparathyroidism,JOURNAL OF BONE AND MINERAL RESEARCH, Issue 7 2004Ajay Bhatia Abstract We describe two female patients, 66 and 36 years of age, with both primary hyperparathyroidism and chondrosarcoma. Case 1 had a chondrosarcoma of the right scapula, and case 2 had chondrosarcoma of the left proximal tibia. Both patients underwent surgical resection of their chondrosarcoma and subsequent parathyroid surgery. Histological analysis of the excised parathyroid in case 1 showed a parathyroid carcinoma and in case 2 showed a parathyroid adenoma. Including these two patients, there is now a total of six cases that have been reported in the literature describing the association between hyperparathyroidism and bone malignancy. We believe that this small number makes it unlikely that there is an association between these two conditions, although we speculate that there may be an underlying genetic basis. [source] Spatial and temporal patterns of bone formation in ectopically pre-fabricated, autologous cell-based engineered bone flaps in rabbitsJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 4 2008Oliver Scheufler Abstract Biological substitutes for autologous bone flaps could be generated by combining flap pre-fabrication and bone tissue engineering concepts. Here, we investigated the pattern of neotissue formation within large pre-fabricated engineered bone flaps in rabbits. Bone marrow stromal cells from 12 New Zealand White rabbits were expanded and uniformly seeded in porous hydroxyapatite scaffolds (tapered cylinders, 10,20 mm diameter, 30 mm height) using a perfusion bioreactor. Autologous cell-scaffold constructs were wrapped in a panniculus carnosus flap, covered by a semipermeable membrane and ectopically implanted. Histological analysis, substantiated by magnetic resonance imaging (MRI) and micro-computerized tomography scans, indicated three distinct zones: an outer one, including bone tissue; a middle zone, formed by fibrous connective tissue; and a central zone, essentially necrotic. The depths of connective tissue and of bone ingrowth were consistent at different construct diameters and significantly increased from respectively 3.1 ± 0.7 mm and 1.0 ± 0.4 mm at 8 weeks to 3.7± 0.6 mm and 1.4 ± 0.6 mm at 12 weeks. Bone formation was found at a maximum depth of 1.8 mm after 12 weeks. Our findings indicate the feasibility of ectopic pre-fabrication of large cell-based engineered bone flaps and prompt for the implementation of strategies to improve construct vascularization, in order to possibly accelerate bone formation towards the core of the grafts. [source] Insulin receptor substrate 1 (IRS-1) plays a unique role in normal epidermal physiology,JOURNAL OF CELLULAR PHYSIOLOGY, Issue 2 2007Marianna Sadagurski Insulin receptor substrate (IRS) proteins play a central role in insulin signaling. Previously we have demonstrated that insulin is essential for normal skin development and function. In the present study we investigated the involvement of the IRS-1 and IRS-2 proteins in skin physiology and in mediating insulin action in skin. For this purpose we have investigated the effects of inactivation of each of the IRSs on skin, studying skin sections and primary skin cells derived from IRS-1 or IRS-2 null mice. We have demonstrated that while the skin of the IRS-2 null mice appeared normal, the skin of the IRS-1 null mice was thinner and translucent. Histological analysis revealed that the thinning of the IRS-1 null skin was a consequence of the thinning of the spinous compartment, consisting of fewer layers. Proliferation of the IRS-1 and IRS-2 null skin epidermal cells was normal. However, the differentiation process of the IRS-1 skin and skin cells was impaired. There was a marked decrease in the induction of the expression of K1, the marker of advanced stages of skin differentiation. In contrary, IRS-2 inactivation had no effects on skin differentiation. In conclusion, we have shown for the first time that IRS-1 but not IRS-2 has an effect on skin formation and development, being one of the main activators of the differentiation process in skin keratinocytes. Furthermore, we suggest that IRS-1 and IRS-2 have distinct roles in skin physiology. J. Cell. Physiol. 213: 519,527, 2007. © 2007 Wiley-Liss, Inc. [source] Susceptibility of GTR-regenerated periodontal attachment to ligature-induced periodontitisJOURNAL OF CLINICAL PERIODONTOLOGY, Issue 5 2004An experiment in the monkey Abstract Aim: This study aimed to compare the susceptibility of guided tissue regeneration (GTR)-regenerated periodontal attachment to ligature-induced periodontitis with that of the pristine periodontium. Methods: Periodontal breakdown was produced in four monkeys by the placement of orthodontic elastics around experimental teeth (test teeth). During a flap operation, the root surfaces were scaled and planed, and a notch indicating the apical termination of scaling and root planing was made in the root surface. Following resection of the crowns and endodontic treatment, an e-PTFE membrane was adapted over the roots. Subsequently, the flaps were sutured to complete closure of the wound (submerged). At membrane removal after 5 weeks, the crowns of the contralateral teeth serving as controls were resected, and the roots treated endodontically during a flap operation. Artificial composite crowns were then placed on both test and control roots. After 3 months of tooth cleaning, cotton floss ligatures were placed passively around both test and control teeth for a period of 6 months. Two weeks later the animals were sacrificed. Results: Histological analysis demonstrated that the instrumented root surfaces of the test teeth were covered by newly formed cementum of the reparative, cellular, extrinsic and intrinsic fiber type, while the cementum on the controls was mainly acellular extrinsic fiber cementum. Histometric assessments demonstrated that similar attachment loss had occurred on test (1.0±0.5 mm) and control roots (1.0±0.4 mm) during the 6 months of ligature-induced plaque accumulation. Conclusion: The results indicate that teeth with a periodontal attachment apparatus formed by GTR is not more susceptible to periodontitis than those with a pristine periodontium. [source] Experimental exposure of zebrafish, Danio rerio (Hamilton), to Mycobacterium marinum and Mycobacterium peregrinum reveals the gastrointestinal tract as the primary route of infection: a potential model for environmental mycobacterial infectionJOURNAL OF FISH DISEASES, Issue 10 2007M J Harriff Abstract The natural route by which fish become infected with mycobacteria is unknown. Danio rerio (Hamilton) were exposed by bath immersion and intubation to Mycobacterium marinum and Mycobacterium peregrinum isolates obtained from diseased zebrafish. Exposed fish were collected over the course of 8 weeks and examined for the presence of mycobacteriosis. Mycobacteria were consistently cultured from the intestines, and often from the livers and spleens of fish exposed by both methods. Mycobacteria were not observed in the gills. Histological analysis revealed that fish infected with M. marinum often developed granulomas accompanied by clinical signs of mycobacteriosis, while infection with M. peregrinum infrequently led to clinical signs of disease. Passage of the bacteria through environmental amoebae (Acanthamoeba castellani) was associated with increased growth of M. peregrinum over the course of 8 weeks, when compared to infection with the bacteria not passed through amoebae. The results provide evidence that zebrafish acquire mycobacteria primarily through the intestinal tract, resulting in mycobacterial dissemination. [source] Formation of cartilage repair tissue in articular cartilage defects pretreated with microfracture and covered with cell-free polymer-based implants,JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 10 2009Christoph Erggelet Abstract The aim of our study was to evaluate the mid-term outcome of a cell-free polymer-based cartilage repair approach in a sheep cartilage defect model in comparison to microfracture treatment. Cell-free, freeze-dried implants (chondrotissue®) made of a poly-glycolic acid (PGA) scaffold and hyaluronan were immersed in autologous serum and used for covering microfractured full-thickness articular cartilage defects of the sheep (n,=,4). Defects treated with microfracture only served as controls (n,=,4). Six months after implantation, cartilage implants and controls were analyzed by immunohistochemical staining of type II collagen, histological staining of proteoglycans, and histological scoring. Histological analysis showed the formation of a cartilaginous repair tissue rich in proteoglycans. Histological scoring documented significant improvement of repair tissue formation when the defects were covered with the cell-free implant, compared to controls treated with microfracture. Immunohistochemistry showed that the cell-free implant induced cartilaginous repair tissue and type II collagen. Controls treated with microfracture showed marginal formation of a mixed-type repair tissue consisting of cartilaginous tissue and fibro-cartilage. Covering of microfractured defects with the cell-free polymer-based cartilage implant is suggested to be a promising treatment option for cartilage defects and improves the regeneration of articular cartilage. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1353,1360, 2009 [source] Histological analysis of achilles tendons in an overuse rat modelJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 6 2008Mark A. Glazebrook Abstract The purpose of this study was to design an animal model that induces histological changes in Achilles tendons consistent with those cited in the literature for human Achilles tendon disease. Sprague-Dawley rats were subjected to 10° uphill treadmill running on a custom-designed rodent treadmill and at a speed of 17 meters per minute for 1 h, five times per week, over a 12-week treatment period. Subsequent histological analysis revealed alterations in the rat Achilles tendon that were generally consistent with those described in the literature for diseased human tendon tissues. These features include: decreased collagen fiber organization, more intense collagen staining, and increased cell nuclei numbers. Interestingly, though, immunohistochemical cell typing suggests that the observed increased cellularity does not include a significant inflammatory component but is secondary to increased numbers of endothelial cells (i.e., vascularization) and fibroblasts. These histological features likely represent a biological repair/remodeling response resulting from overuse running. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:840,846, 2008 [source] Regulation of embryonic endochondral ossification by Smurf2JOURNAL OF ORTHOPAEDIC RESEARCH, Issue 5 2008Qiuqian Wu Abstract Smurf2 is an E3 ubiquitin ligase that targets TGF-, receptor activated Smad2 and Smad3 for the proteasome in primary articular chondrocytes, thus stimulating their hypertrophic differentiation. Comparatively, how Smurf2 functions in growth plate chondrocytes in a developing long bone is an open question. In this study, we measured the mRNA levels of endogenous Smurf2 and type X collagen in chick growth plate at different embryonic stages to monitor the correlation between the level of Smurf2 expression and chondrocyte maturational stage. We found that high levels of Smurf2 were associated with the differentiative and proliferative stages, while Smurf2 levels were thereafter decreased as the chondrocytes matured toward hypertrophy. In addition, we injected Smurf2 -RCAS into chick wing buds at HH stage 20,23 and examined how the ectopic overexpression of Smurf2 in condensing chondrogenic mesenchyme affects the subsequent process of chondrocyte maturation and ossification during embryonic development. Histological analysis showed that overexpression of Smurf2 in a developing wing bud accelerated chondrocyte maturation and endochondral ossification, which may result from a decrease in TGF-, signaling in the infected chondrocytes with Smurf2 -RCAS. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:704,712, 2008 [source] Ultrastructural findings after intraarticular application of hyaluronan in a canine model of arthropathyJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 4 2000W. Wenz We investigated the effect of intraarticularly applied hyaluronic acid (hyaluronan) on the cartilaginous structure of experimentally induced chondromalacia patellae in dogs. For the induction of chondromalacia, we used the Pond-Nuki technique, which involved severance and resection of the anterior cruciate ligament, as a canine model of arthropathy in 27 foxhounds (three groups of nine animals each). In a pilot study, we evaluated the effect of resection of the anterior cruciate ligament with no therapy. Patellar specimens were retrieved at 3, 6, and 12 weeks postoperatively. Subsequently, we compared a treatment group that received intraarticular injections of hyaluronan with a placebo group that received saline solution. The groups were compared at 3, 6, and 12 weeks postoperatively. Three animals from the treatment and placebo groups received five injections of hyaluronan during one of the 4-week intervals (weeks 3,6, 6,9, or 12,15). Specimens were retrieved 5 weeks after the last injection. In both groups, the uninvolved contralateral knee served as a control. The specimens were taken from the medial and lateral patellar poles. Histological analysis included light microscopy and transmission electron microscopy. The structural and ultrastructural changes were assessed qualitatively and were quantified with use of a modified Mankin score. Our results indicate that chondromalacia patellae may be induced with the Pond-Nuki technique. We found a significant reduction (p < 0.01) of cartilaginous lesions in the hyaluronan group compared with the placebo group. Our results suggest that intraarticularly applied hyaluronan is effective in delaying the degenerative process of cartilage degradation. Therefore, we conclude that the use of hyaluronan may be indicated during the early stages of chondromalacia. [source] In vitro and in vivo cytokeratin patterns of expression in bioengineered human periodontal mucosaJOURNAL OF PERIODONTAL RESEARCH, Issue 5 2009I. Garzón Background and Objective:, Development of human oral mucosa substitutes by tissue engineering may provide new therapeutic tools for the management of periodontal diseases. In this study we evaluated a fibrin,agarose human oral mucosa substitute both in vitro and in vivo. Material and Methods:,In vitro bioengineered oral mucosa substitutes were developed from irrelevant biopsy samples of human oral gingiva. In vivo evaluation of the constructed tissues was performed by implantation into athymic nude mice. The expression of several epithelial markers was assessed by microarray analysis and immunohistochemistry. Results:, Bioengineered oral mucosa samples kept in vitro developed a multilayered epithelium that expressed several cytokeratins, including some markers of simple epithelia (cytokeratins 7, 8 and 18), along with markers of stratified epithelia (cytokeratins 5 and 13) and of cell proliferation (proliferating cell nuclear antigen). Bioengineered tissues grafted in vivo onto nude mice exhibited very good biointegration with the host, showing a cytokeratin expression pattern that was very similar to that of normal native oral mucosa controls. Histological analysis of the artificial tissues demonstrated that oral mucosa substitutes evaluated in vivo were structurally mature, showing some typical structures of human native oral mucosa such as rete ridges and chorial papillae, along with numerous blood vessels at the fibrin,agarose stromal substitute. These structures were absent in samples evaluated in vitro. Conclusion:, The results indicate that this model of human oral mucosa, constructed using fibrin,agarose scaffolds, shows similarities to native oral mucosa controls and imply that bioengineered oral mucosa substitutes could eventually be used clinically. [source] Extracellular matrix,polymer hybrid materials produced in a pulsed-flow bioreactor systemJOURNAL OF TISSUE ENGINEERING AND REGENERATIVE MEDICINE, Issue 3 2009Cecilia Aulin Abstract Cell adhesion, interaction with material, cell proliferation and the production of an extracellular matrix (ECM) are all important factors determining the successful performance of an engineered scaffold. Scaffold design should aim at creating structures which can guide cells into forming new, functional tissue. In this study, the concept of in situ deposition of ECM by human dermal fibroblasts onto a compliant, knitted poly (ethyleneterephtalate) support is demonstrated, creating in vitro produced ECM polymer hybrid materials for tissue engineering. Comparison of cells cultured under static and dynamic conditions were examined, and the structure and morphology of the materials so formed were evaluated, along with the amount collagen deposited by the seeded cells. In vitro produced ECM polymer hybrid scaffolds could be created in this way, with the dynamic culture conditions increasing ECM deposition. Histological analysis indicated a homogenous distribution of cells in the 1 mm thick scaffold, surrounded by a matrix-like structure. ECM deposition was observed throughout the materials wigh 81.6 µg/cm2 of collagen deposited after 6 weeks. Cell produced bundles of ECM fibres bridged the polymer filaments and anchored cells to the support. These findings open hereto unknown possibilities of producing materials with structure designed by engineering together with biochemical composition given by cells. Copyright © 2009 John Wiley & Sons, Ltd. [source] Photoacoustic monitoring of neovascularities in grafted skinLASERS IN SURGERY AND MEDICINE, Issue 3 2006Mutsuo Yamazaki MS Abstract Background and Objective In skin grafting, evaluation of graft adhesion to the recipient site in the early postgrafting period is important. However, conventional diagnoses such as visual observation and thermography required about 1 week to obtain results and these methods cannot give quantitative information on the adhesion of a skin graft. We proposed a new method for monitoring adhesion of grafted skin that is based on measurement of photoacoustic signals. To investigate the validity of the method, we performed experiments using rat autografts models. Study Design/Materials and Methods Grafted skin in a rat was irradiated with 200 µJ, 532-nm nanosecond laser pulses, and photoacoustic signals were detected with a piezoelectric transducer placed on the skin at various postgrafting time. Temporal profiles of the signals were converted to depth profiles using an assumed sound velocity of 1,500 m/second. Histological analysis was performed to observe neovascularities formed in the grafts. Results At 6 hours postgrafting, a photoacoustic signal peak appeared in the depth region corresponding to the graft. The results of histological analysis also showed formation of neovascularities in the graft after 6 hours postgrafting, indicating that photoacoustic signal peaks observed in the graft originated from the neovascularities, which are an indication of graft adhesion. For up to 24 hours postgrafting, no significant difference was observed between the results of visual observation and laser Doppler imaging of the same grafted skins. Conclusion We have demonstrated that photoacoustic signals originating from neovascularities in grafts can be sensitively detected in the early postgrafting period, suggesting the validity of photoacoustic measurement for adhesion monitoring of skin grafts. Lasers Surg. Med. 38:235,239, 2006. © 2006 Wiley-Liss, Inc. [source] Hyperbaric oxygen attenuation of lipopolysaccharide-induced acute lung injury involves heme oxygenase-1ACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 9 2005T.-Y. Huang Background:, Hyperbaric oxygen (HBO) attenuates lipopolysaccharide (LPS)-induced acute lung injury. This beneficial effect of HBO involves inhibition of inducible nitric oxide synthase (iNOS) expression and subsequent nitric oxide (NO) biosynthesis. We sought to investigate the role of heme oxygenase-1 (HO-1) on this HBO inhibition of iNOS induction and acute lung injury in septic rat lungs. Methods:, Before the experiment, 72 rats were randomly allocated to receive HBO or air treatment. With or without HBO pre-treatment, the rats were further divided into the following subgroups (n = 6): (i) LPS injection, (ii) normal saline (N/S) injection, (iii) hemin (a HO-1 inducer) plus LPS, (iv) hemin alone, (v) tin protoporphyrin (SnPP; a HO-1 inhibitor) plus LPS, and (vi) SnPP alone. All rats were maintained for 6 h and then sacrificed with a high-dose pentobarbital injection. Lung injuries and relevant enzymes expression were thus assayed. Results:, Histological analysis, PMNs/alveoli ratio, and wet/dry weight ratio measurements demonstrated that LPS caused significant lung injury and HBO and/or hemin significantly attenuated this LPS-induced lung injury. Increased pulmonary iNOS expression and NO production were associated with lung injury. Induction of HO-1, by HBO and/or hemin, significantly attenuated this LPS-induced iNOS expression and acute lung injury. SnPP, on the contrary, offset the effects of HBO and worsened the LPS-induced lung injury. Conclusions:, HBO may act through inhibiting pulmonary iNOS expression to attenuate LPS-induced acute lung injury in septic rats. Furthermore, this HBO attenuation of iNOS expression involves HO-1 induction. [source] Xenon-129 MR imaging and spectroscopy of rat brain using arterial delivery of hyperpolarized xenon in a lipid emulsionMAGNETIC RESONANCE IN MEDICINE, Issue 2 2001Guillaume Duhamel Abstract Hyperpolarized 129Xe dissolved in a lipid emulsion constitutes an NMR tracer that can be injected into the blood stream, enabling blood-flow measurement and perfusion imaging. A small volume (0.15 ml) of this tracer was injected in 1.5 s in rat carotid and 129Xe MR spectra and images were acquired at 2.35 T to evaluate the potential of this approach for cerebral studies. Xenon spectra consistently showed two resonances, at 194.5 ppm and 199.0 ppm relative to the gas peak. The signal-to-noise ratio (SNR) obtained for the two peaks was sufficient (ranging from 12 to 90) to follow their time courses. 2D transverse-projection xenon images were obtained with an in-plane resolution of 900 ,m per pixel (SNR range 8,15). Histological analysis revealed no brain damage except in two rats that had received three injections. Magn Reson Med 46:208,212, 2001. © 2001 Wiley-Liss, Inc. [source] MIB-1 immunolabeling: A valuable marker in prediction of benign recurring meningiomasNEUROPATHOLOGY, Issue 5 2007Mahesha Vankalakunti Histological analysis has limited value to predict biological behavior of meningiomas. We investigated the utility of cell proliferative indicator in the evaluation of histologically benign meningiomas. We selected 25 benign non-recurrent meningiomas, 15 benign recurrent meningiomas after complete surgical resection, 30 atypical meningiomas, and 15 anaplastic meningiomas out of 384 cases studied. MIB-1 Labeling Index was evaluated by two methods: Highest Labeling Index (HLI) and Random Labeling Index (RLI). There was no dependable histological parameter to predict recurrence among benign-looking meningiomas. HLI had significant difference when compared with RLI in all categories. The mean MIB-1 HLI values ± SD were 3.47 ± 2.0% for benign meningiomas, 5.08 ± 4.0% for atypical meningiomas and 11.66 ± 7.06% for anaplastic meningiomas. In comparison, the mean MIB-1 HLI of benign non-recurrent meningiomas were 2.66 ± 1.7% and with recurrence were 4.21 ± 2.78% (P = 0.0339). Using receiver operating characteristic, it was seen that neoplasm recurred with the MIB-1 HLI of > 2.6 having the sensitivity of 64.6% and specificity of 68% among benign (grade I) meningiomas. MIB-1 positive tumor cells were maximally aggregated at the periphery of excised specimen. MIB-1 HLI, integrated with standard histopathology can provide better information about the disease biological nature in benign meningiomas. [source] A double three-step theory of brain metastasis in mice: the role of the pia mater and matrix metalloproteinasesNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2007N. Saito The brain is frequently affected by the spread of lung cancer, and haematogenous metastasis is a common route to brain metastasis. We therefore developed an isogenic brain metastasis model of lung cancer to use the Lewis lung carcinoma cell line and analysed dynamics of neoplastic cells after extravasation. Histological analysis revealed two characteristic patterns: metastatic foci exhibiting an angiocentric pattern were designated ,perivascular proliferations'; neoplastic cells infiltrating the brain parenchyma were designated ,invasive proliferations'. Electron microscopic observation of perivascular proliferations showed that neoplastic cells were confined to the perivascular space. In invasive proliferations, however, fragments of collagen fibre were observed in the gaps between neoplastic cells, indicating that the neoplastic cells had disintegrated the pia-glial membrane. We analysed the expressions of matrix metalloproteinase-2 (MMP-2) and MMP-9 by using both immunohistochemical analysis and real-time polymerase chain reaction analysis. MMP-2 expression was significantly higher in invasive proliferations. MMP-9 expression was significantly higher in day 7, but there was no significant difference in day 11. The pia-glial membrane and perivascular space are the barriers that neoplastic cells must overcome to infiltrate the brain. In conclusion, our findings suggest that brain metastasis requires two distinct processes. [source] Autophagic vacuolar myopathy in twin girlsNEUROPATHOLOGY & APPLIED NEUROBIOLOGY, Issue 3 2006J. L. Holton Hereditary autophagic vacuolar myopathy (AVM) may occur in several diseases including the rimmed vacuolar myopathies, acid maltase deficiency, Danon disease, infantile autophagic vacuolar myopathy and X-linked myopathy with excessive autophagy (XMEA). In the latter three conditions the vacuoles are lined by membranes with sarcolemmal features. We present two unusual cases of autophagic vacuolar myopathy in twin girls born at term with no family history of neurological disease. After initial normal developmental milestones they developed progressive leg weakness and wasting with contractures from the age of 12 years. Investigations showed raised CK, normal female karyotype, normal acid maltase activity, normal nerve conduction and myopathic EMG features. Frozen sections of skeletal muscle were stained using routine tinctorial and histochemical methods. Immunohistochemical staining for spectrin, merosin, dystrophin, complement membrane attack complex and sarcoglycans was performed and ultrastructural examination undertaken. Direct sequence analysis of the lamp-2 gene using genomic DNA extracted from lymphocytes was performed. Histological analysis of the muscle biopsies demonstrated myofibres with vacuoles lacking glycogen and lipid many of which were delineated using immunohistochemistry for merosin, dystrophin and sarcoglycans. Ultrastructural examination showed duplication of the myofibre basal lamina with associated autophagic material. Vacuoles within myofibres were either membrane bound containing autophagic material or lined by plasma membrane and basal lamina. Intermyofibrillar glycogen was increased. Sequence analysis of the coding region and intron/exon boundaries of the lamp-2 gene was normal. This is the first report of female cases of AVM with sarcolemmal features. We suggest that these patients may represent manifesting carriers of XMEA, or alternatively, a new form of disease with a similar phenotype having autosomal recessive inheritance. [source] | |||||||||||||||||||||||||||||||||||||