Subcutaneous Region Research Articles

Expression of inflammation-related genes is associated with adipose tissue location in horses

BackgroundIn humans, adipose tissue (AT) originating from different depots shows varying gene expression profiles. In horses, the risk of certain metabolic disorders may also be influenced by the impact of specific AT depots. Macrophage infiltration in human and rat AT is considered to be a source of inflammatory changes. In horses, this relationship has not been extensively studied yet. Reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR), a useful method to evaluate differences in mRNA expression across different tissues, can be used to evaluate differences between equine AT depots. For a correct interpretation of the RT-qPCR results, expression data have to be normalized by the use of validated reference genes. The main objectives of this study were to compare mRNA expression of inflammation-related genes, as well as adipocyte morphology and number between different equine AT depots; and in addition, to investigate the presence of antigen presenting cells in equine AT and any potential relationship with adipokine mRNA expression.ResultsIn this study, the mRNA expression of inflammation-related genes (leptin, chemokine ligand 5, interleukin 1β, interleukin 6, interleukin 10, adiponectin, matrix metalloproteinase 2, and superoxide dismutase 2) and candidate reference gene stability was investigated in 8 different AT depots collected from the nuchal, abdominal (mesenteric, retroperitoneal, and peri-renal) and subcutaneous (tail head and loin) AT region. By using GeNorm analysis, HPRT1, RPL32, and GAPDH were found to be the most stable genes in equine AT. The mRNA expression of leptin, chemokine ligand 5, interleukin 10, interleukin 1β, adiponectin, and matrix metalloproteinase 2 significantly differed across AT depots (P < 0.05). No significant AT depot effect was found for interleukin 6 and superoxide dismutase 2 (P > 0.05). Adipocyte area and number of antigen presenting cells per adipocyte significantly differed between AT depots (P < 0.05).ConclusionsAdipose tissue location was associated with differences in mRNA expression of inflammation-related genes. This depot-specific difference in mRNA expression suggests that the overall inflammatory status of horses could be partially determined by the relative proportion of the different AT depots.

Surgical Extirpation of Glomus Tumor from Rare Localization on the Upper Extremity

Objective. To report on a very rare case of a glomus tumor manifested on the upper arm in a healthy young male patient. Case Presentation and Intervention. A 22-year-old male patient presented with bluish multifocal venous malformation on the left upper arm and was admitted for venous malformation excision. Pain, discomfort, and upper arm paraesthesia had been present for almost 6 years. Ultrasonography revealed septet tumor without blood flow in the subcutaneous region of anterior aspect of the upper arm. A multifocal venous malformation approximately 5–10 mm in diameter was excised. Histological examination showed dilated vascular area with proliferated glomus cells with round nucleus in the wall of dilated vascular structures. Based on histological examination, the final diagnosis was made as “glomangioma.” Conclusion. Histological examination is the only method that can establish final diagnosis. Currently, the only available treatment for this type of tumor is surgical excision.

Scan Quality and Entrance Skin Dose in Thoracic CT: A Comparison between Bismuth Breast Shield and Posteriorly Centered Partial CT Scans.

Objectives. To compare the effectiveness of the bismuth breast shield and partial CT scan in reducing entrance skin dose and to evaluate the effect of the breast shield on image quality (IQ). Methods. Nanodots were placed on an adult anthropomorphic phantom. Standard chest CT, CT with shield, and partial CT were performed. Nanodot readings and effective doses were recorded. 50 patients with chest CTs obtained both with and without breast shields were reviewed. IQ was evaluated by two radiologists and by measuring Hounsfield units (HUs) and standard deviation (SD) of HU in anterior subcutaneous region. Results. Breast shield and the partial CT scans reduced radiation to the anterior chest by 38% and 16%, respectively. Partial CT increased dose to the posterior chest by 37% and effective dose by 8%. Change in IQ in shield CT was observed in the anterior chest wall. Significant change in IQ was observed in 5/50 cases. The shield caused an increase of 20 HU (P = 0.021) and a 1.86 reduction in SD of HU (P = 0.027) in the anterior compared to posterior subcutaneous regions. Summary. Bismuth breast shield is more effective than the partial CT in reducing entrance skin dose while maintaining image quality.

El proteoma del tejido adiposo subcutáneo muestra heterogeneidad anatómica

BackgroundHuman subcutaneous (SQ) white adipose tissue (WAT) can vary according to its anatomical location, with subsequent differences in its proteomic profile. Patients and methodsSQ-WAT aspirates were obtained from six overweight (BMI>25kg/m2) women who underwent extensive liposuction. SQ-WAT was removed from six different locations (upper abdominal, lower abdominal, thigh, back, flank, and hip), and the protein profiles were determined by two-dimensional gel electrophoresis. In addition, the proteomic profiles of upper abdominal and hip SQ-WAT were subjected to further analysis, comparing samples obtained from two layers of WAT (deep and superficial). ResultsTwenty one protein spots showed differential intensities among the six defined anatomical locations, and 14 between the superficial and the deep layer. Among the proteins identified were, vimentin (structural protein), heat-shock proteins (HSPs), superoxide-dismutase (stress-resistance/chaperones), fatty-acid-binding protein (FABP) 4, and alpha-enolase (lipid and carbohydrate metabolism), and ATP-synthase (energy production). Among the WAT samples analyzed, the back sub-depot showed significant differences in the levels of selected proteins when compared to the other locations, with lower level of expression of several proteins involved in energy production and metabolism (ATP-synthase, alpha-enolase, HSPs and FABP-4). ConclusionsThe levels of several proteins in human SQ-WAT are not homogeneous between different WAT depots. These changes suggest the existence of inherent functional differences in subcutaneous fat depending upon its anatomical location. Thus, caution must be used when extrapolating data from one subcutaneous WAT region to other depots.

Automated unsupervised multi‐parametric classification of adipose tissue depots in skeletal muscle

To introduce and validate an automated unsupervised multi-parametric method for segmentation of the subcutaneous fat and muscle regions to determine subcutaneous adipose tissue (SAT) and intermuscular adipose tissue (IMAT) areas based on data from a quantitative chemical shift-based water-fat separation approach. Unsupervised standard k-means clustering was used to define sets of similar features (k = 2) within the whole multi-modal image after the water-fat separation. The automated image processing chain was composed of three primary stages: tissue, muscle, and bone region segmentation. The algorithm was applied on calf and thigh datasets to compute SAT and IMAT areas and was compared with a manual segmentation. The IMAT area using the automatic segmentation had excellent agreement with the IMAT area using the manual segmentation for all the cases in the thigh (R(2): 0.96) and for cases with up to moderate IMAT area in the calf (R(2): 0.92). The group with the highest grade of muscle fat infiltration in the calf had the highest error in the inner SAT contour calculation. The proposed multi-parametric segmentation approach combined with quantitative water-fat imaging provides an accurate and reliable method for an automated calculation of the SAT and IMAT areas reducing considerably the total postprocessing time.

Sarcomas of the scalp: A comparison of two lesions

Sarcomas of the scalp: A comparison of two lesions

Glucose-lowering Effect of Insulin Degludec is Independent of Subcutaneous Injection Region

Glucose-lowering Effect of Insulin Degludec is Independent of Subcutaneous Injection Region

Efeitos do treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo

Há poucos estudos analisando a importante relação entre o exercício físico, agudo e crônico, e alterações metabólicas decorrentes do hipertireoidismo. O objetivo do presente estudo foi analisar o efeito de quatro semanas de treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo experimental. Foram utilizados 45 ratos da linhagem Wistar, divididos aleatoriamente em quatro grupos: Controle Sedentário (CS) - administrados com salina durante o período experimental, não praticaram exercício físico (n = 12); Controle Treinado (CT) - administrados com salina, participaram do treinamento (n = 11); Hipertireoidismo Sedentário (HS) - induzidos ao hipertireoidismo, não praticaram exercício físico (n = 12); e Hipertireoidismo Treinado (HT) - induzidos ao hipertireoidismo, participaram do treinamento (n = 10). O treinamento aeróbio teve duração de quatro semanas, cinco vezes na semana, com duração de uma hora por sessão. Após o término do período experimental todos os ratos foram anestesiados em câmara de CO2 até sua sedação. Coletaram-se amostras de sangue para dosagem de colesterol total, triglicerídeos, HDL-colesterol e LDL-colesterol e hormônio T3; e amostras do coração, fígado, músculo gastrocnêmio e tecido adiposo das regiões mesentérica, retroperitonial e subcutânea para pesagem e dosagem de triglicerídeos. Para análise estatística utilizou-se ANOVA two-way, seguida do post hoc LSD de Fischer. Observaram-se menores valores de AGL no grupo HS quando comparado ao CS. O grupo HS teve nível de triglicerídeos significativamente superior nas regiões mesentérica, do gastrocnêmio e retroperitonial quando comparado com os grupos CS e CT, e apenas o tecido adiposo da região retroperitonial apresentou diferenças significativas na qual o grupo HT apresentou menor peso quando comparado com o grupo CS. Pode-se concluir que os ratos hipertireoidicos apresentaram perfil lipídico diferente dos ratos controle, e o treinamento aeróbio em ratos Wistar pode ter alterado o perfil lipídico dos animais com hipertireoidismo experimental quando comparados com o grupo sedentário e grupos controle.

The Effect of the Microenvironment Created by a Titanium Mesh Cage on Subcutaneous Experimental Bone Formation and Inhibition of Absorption

We attempted to form ectopic bone under the skin of rats without adding any extrinsic bone-inducing growth factors or cytokines using bone marrow stromal cells (BMSCs), a collagen scaffold and a titanium mesh cage. We set up a space made up of a cage inserted into the subcutaneous region of rats’ backs, where we could eliminate the possible influence of residual bone tissue on bone induction. We filled this space with a collagen matrix containing BMSCs. At week 8 and month 6 after implantation, the specimens were removed and observed histologically, histochemically and enzyme histochemically. As a result, bone tissue was identified in each case within the titanium cages, even though we had not used bone-inducing chemical substances. Bone generation was not found in test cases without a cage. Enhanced green fluorescence protein (EGFP) labeling of the implanted BMSCs clearly showed that these cells differentiated into osteoblasts and subsequently into osteocytes in the formed bone tissue. Host cells without EGFP labeling were also confirmed to be involved in bone formation. Six months after transplantation, the implanted cells were still present in the generated bone, and no significant resorption of the generated bone was observed. These results indicate that the physically stable spatial microenvironment created by the cage in vivo plays an important role in bone formation and inhibition of its resorption, which we refer to as the ‘cage effect’.

Sketched x-rays: Calcinosis universalis

Calcinosis universalis (CU) is a known complication of dermatomyositis manifesting as calcified nodules and plaques localized in subcutaneous tissue, fascial planes, tendons, or intramuscular regions. We report a case and image of CU in a 9-year-old boy diagnosed with juvenile dermatomyositis (JDM).

Cell-Engineered Human Elastic Chondrocytes Regenerate Natural Scaffold In Vitro and Neocartilage with Neoperichondrium in the Human Body Post-Transplantation

We have developed a unique method that allows us to culture large volumes of chondrocyte expansion from a small piece of human elastic cartilage. The characteristic features of our culturing method are that fibroblast growth factor-2 (FGF2), which promotes proliferation of elastic chondrocytes, is added to a culture medium, and that cell-engineering techniques are adopted in the multilayered culture system that we have developed. We have subsequently discovered that once multilayered chondrocytes are transplanted into a human body, differentiation induction that makes use of surrounding tissue occurs in situ, and a large cartilage block is obtained through cartinogenesis and matrix formation. We have named this method two-stage transplantation. We have clinically applied this transplantation method to the congenital ear defect, microtia, and reported successful ear reconstruction. In our present study, we demonstrated that when FGF2 was added to elastic chondrocytes, the cell count increased and the level of hyaluronic acid, which is a major extracellular matrix (ECM) component, increased. We also demonstrated that these biochemical changes are reflected in the morphology, with the elastic chondrocytes themselves producing a matrix and fibers in vitro to form a natural scaffold. We then demonstrated that inside the natural scaffold thus formed, the cells overlap, connect intercellularly to each other, and reconstruct a cartilage-like three-dimensional structure in vitro. We further demonstrated by immunohistochemical analysis and electron microscopic analysis that when the multilayered chondrocytes are subsequently transplanted into a living body (abdominal subcutaneous region) in the two-stage transplantation process, neocartilage and neoperichondrium of elastic cartilage origin are regenerated 6 months after transplantation. Further, evaluation by dynamic mechanical analysis showed the regenerated neocartilage to have the same viscoelasticity as normal auricular cartilage. Using our multilayered culture system supplemented with FGF2, elastic chondrocytes produce an ECM and also exhibit an intercellular network; therefore, they are able to maintain tissue integrity post-transplantation. These findings realized a clinical application for generative cartilage surgery.

Transfer Printing of Cell Layers with an Anisotropic Extracellular Matrix Assembly using Cell‐Interactive and Thermosensitive Hydrogels

AbstractThe structure of tissue plays a critical role in its function and therefore a great deal of attention has been focused on engineering native tissue‐like constructs for tissue engineering applications. Transfer printing of cell layers is a new technology that allows controlled transfer of cell layers cultured on smart substrates with defined shape and size onto tissue‐specific defect sites. Here, the temperature‐responsive swelling‐deswelling of the hydrogels with groove patterns and their versatile and simple use as a template to harvest cell layers with anisotropic extracellular matrix assembly is reported. The hydrogels with a cell‐interactive peptide and anisotropic groove patterns are obtained via enzymatic polymerization. The results show that the cell layer with patterns can be easily transferred to new substrates by lowering the temperature. In addition, multiple cell layers are stacked on the new substrate in a hierarchical manner and the cell layer is easily transplanted onto a subcutaneous region. These results indicate that the evaluated hydrogel can be used as a novel substrate for transfer printing of artificial tissue constructs with controlled structural integrity, which may hold potential to engineer tissue that can closely mimic native tissue architecture.

Behavioral meaningful opioidergic stimulation activates kappa receptor gene expression.

The periaqueductal gray (PAG) has been reported to be a location for opioid regulation of pain and a potential site for behavioral selection in females. Opioid-mediated behavioral and physiological responses differ according to the activity of opioid receptor subtypes. The present study investigated the effects of the peripheral injection of the kappa-opioid receptor agonist U69593 into the dorsal subcutaneous region of animals on maternal behavior and on Oprk1 gene activity in the PAG of female rats. Female Wistar rats weighing 200-250 g at the beginning of the study were randomly divided into 2 groups for maternal behavior and gene expression experiments. On day 5, pups were removed at 7:00 am and placed in another home cage that was distant from their mother. Thirty minutes after removing the pups, the dams were treated with U69593 (0.15 mg/kg, sc) or 0.9% saline (up to 1 mL/kg) and after 30 min were evaluated in the maternal behavior test. Latencies in seconds for pup retrieval, grouping, crouching, and full maternal behavior were scored. The results showed that U69593 administration inhibited maternal behavior (P < 0.05) because a lower percentage of U69593 group dams showed retrieval of first pup, retrieving all pups, grouping, crouching and displaying full maternal behavior compared to the saline group. Opioid gene expression was evaluated using real-time reverse-transcription polymerase chain reaction (RT-PCR). A single injection of U69593 increased Oprk1 PAG expression in both virgin (P < 0.05) and lactating female rats (P < 0.01), with no significant effect on Oprm1 or Oprd1 gene activity. Thus, the expression of kappa-opioid receptors in the PAG may be modulated by single opioid receptor stimulation and behavioral meaningful opioidergic transmission in the adult female might occur simultaneously to specific changes in gene expression of kappa-opioid receptor subtype. This is yet another alert for the complex role of the opioid system in female reproduction.

Functional annotation of the human fat cell secretome

Context: Recent secretome analyses suggest that human fat cells secrete hundreds of proteins (adipokines).Objective: We made an overall analysis of their potential functional importance.Materials and methods: A secretome of 347 adipokines was evaluated by in silico analysis of their expression during adipocyte differentiation, regulation by obesity and adipose region. The gene expression in human adipose tissue was investigated in microarray studies using samples from different adipose depots from lean or obese patients.Results: 60% of the adipokines were regulated by obesity and 50% between visceral and subcutaneous adipose region. Eight adipokines, all novel, scored particularly high in the in silico analysis. Among those, four were both regulated by obesity and adipose region, namely WNT1-inducible-signaling pathway protein 2, transmembrane glycoprotein NMB, inter-alpha-trypsin inhibitor heavy chain H5, and complement C4-A. Furthermore, many adipokines were extracellular matrix proteins.Conclusion: Several novel adipokines have potential important functional features warranting in depth analysis.

Neurolymphomatosis: A Case Series of Clinical Manifestations, Treatments, and Outcomes (P04.187)

Objective: Our goal was to ascertain common factors to render earlier diagnosis, and prognostic factors to predict response to therapy. Background Neurolymphomatosis involves infiltration of malignant lymphocytes into the peripheral nervous system, specifically cranial nerves, roots, plexuses, and/or peripheral nerves. It is distinct from more common neurological complications related to chemotherapy, irradiation, paraneoplastic disorders, and leptomeningeal carcinomatosis. Design/Methods: We review five patients who developed neurolymphomatosis at M.D. Anderson Cancer Center between 2010 and 2011. Clinical, radiologic, and laboratory data were extracted from their medical records. Results: The average age at onset was 48 (range 26 - 76) with primary diagnosis being non-Hodgkin9s lymphoma in three (Burkitt9s, large B-cell) and leukemia in two (AML, CML). Initial symptoms included weakness (5/5), pain (3/5), and sensory change (2/5) and localized to lower extremities (3/5), upper extremities (2/5), unilateral (4/5), bilateral (1/5), and cranial nerve (1/5). Physical exam findings included weakness (5/5), sensory disturbance (5/5), atrophy (4/5), hypotonia (2/5), and hyporeflexia (5/5). Three patients demonstrated MRI abnormalities with clinical correlation, affecting neural foramina (1/5), paraspinal (2/5), or subcutaneous (1/5) regions; no patients had imaging evidence of parenchymal, spinal cord, or leptomeningeal pathology. All patients had positive EMG/NCS and diagnoses included mononeuritis multiplex, multifocal plexopathy, demyelinating polyneuropathy, and chronic axonal polyradiculoneuropathy. One patient had positive CSF cytology; PET was performed and positive in four patients and no nerve biopsies or autopsies were performed. Therapies included systemic (5/5) and intrathecal chemotherapy (4/5), immunomodulators (2/5), and plasma exchange (1/5); no patients underwent radiotherapy. Mortality was 40% with average survival from neurologic presentation 6 months (range 1–12 months); the other patients progressed despite treatment. Neither age, gender, malignancy type, recurrence, positive CSF/imaging/EMG, nor intervention correlated with worse prognosis. Conclusions: Further studies are warranted to define risk for developing neurolymphomatosis and identify factors affecting outcome. Disclosure: Dr. Gildersleeve has nothing to disclose. Dr. Hormozdi has nothing to disclose. Dr. Kamiya Matsuoka has nothing to disclose. Dr. Woodman has nothing to disclose.

Serum concentrations of phthalate metabolites are related to abdominal fat distribution two years later in elderly women

BackgroundPhthalates, commonly used to soften plastic goods, are known PPAR-agonists affecting lipid metabolism and adipocytes in the experimental setting. We evaluated if circulating concentrations of phthalates were related to different indices of obesity using data from the Prospective Investigation of the Vasculature in Uppsala Seniors (PIVUS) study. Data from both dual-energy X-ray absorptiometry (DXA) and abdominal magnetic resonance imaging (MRI) were used.Methods1,016 subjects aged 70 years were investigated in the PIVUS study. Four phthalate metabolites were detected in the serum of almost all subjects (> 96%) by an API 4000 liquid chromatograph/tandem mass spectrometer. Abdominal MRI was performed in a representative subsample of 287 subjects (28%), and a dual-energy X-ray absorptiometry (DXA)-scan was obtained in 890 (88%) of the subjects two year following the phthalate measurements.ResultsIn women, circulating concentrations of mono-isobutyl phthalate (MiBP) were positively related to waist circumference, total fat mass and trunk fat mass by DXA, as well as to subcutaneous adipose tissue by MRI following adjustment for serum cholesterol and triglycerides, education, smoking and exercise habits (all p < 0.008). Mono-methyl phthalate (MMP) concentrations were related to trunk fat mass and the trunk/leg-ratio by DXA, but less powerful than MiBP. However, no such statistically significant relationships were seen in men.ConclusionsThe present evaluation shows that especially the phthalate metabolite MiBP was related to increased fat amount in the subcutaneous abdominal region in women measured by DXA and MRI two years later.

Relation of depot-specific adipose inflammation to insulin resistance in human obesity

BACKGROUND:A low-grade state of adipose tissue inflammation associated with obesity has been linked to mechanisms of systemic metabolic dysfunction. However, the relation of clinical phenotypes to depot-specific inflammation has not been well examined in human obesity.OBJECTIVE:To characterize the inflammatory status of subcutaneous and visceral fat depots, as assessed by tissue presence of macrophage crown-like structures (CLS) as a hallmark of chronic inflammation, and determine the relation of systemic insulin resistance to inflammatory abnormalities in subcutaneous and visceral fat.METHODS:We collected adipose tissue simultaneously from subcutaneous and visceral (omental and mesenteric) depots in 92 obese participants (age 42±11 years; BMI⩾30 kg m−2) during planned bariatric surgery. Using immunohistochemistry, we categorized individuals as CLS+ or CLS− based on the presence or absence, respectively, of macrophage CLS in subcutaneous (CLSs), omental (CLSo) and mesenteric (CLSm) adipose depots.RESULTS:The majority of participants exhibited adipose tissue inflammation manifest by the presence of CLS (CLS+) in both subcutaneous and intra-abdominal visceral depots. CLS status in subcutaneous fat was highly sensitive and modestly specific for inflammation of visceral fat. In multivariable models, plasma insulin and homeostatis model assessment levels were positively associated with CLS+ status in all depots independent of age, waist circumference, BMI and type 2 diabetes, and worsened with the increasing number of adipose regions involved.CONCLUSIONS:In severely obese participants, systemic insulin resistance is linked to adipose inflammation in both subcutaneous and visceral depots. The findings suggest that examination of subcutaneous regions that are more easily accessible by transcutaneous biopsy may prove useful in clinical studies designed to investigate adipose phenotypes in relation to human disease.

Cruris Posteriorda Enfekte Primer Musküler Hidatik Hastalığı, Çok Nadir Bir Lokalizasyon

A parasitic tapeworm, Echinococcus, causes hydatid disease. Disease is mostly seen in the abdominal and thoracic organs but can be seen in other tissues as well. Hydatid cysts of the extremities mostly present themselves in the subcutaneous region. Muscular hydatid cysts generally occur secondary to abdominal or thoracic hydatid disease. Primary muscular hydatidosis is a very rare disease and mostly seen in the gluteal and thigh muscles. Distal muscles are very rare localizations for primary muscular hydatidosis cases. In the treatment, surgical excision is the gold standard. Medical treatment is generally preferred after surgery. Here, we present an isolated infected primary muscular hydatid cyst in the deep posterior cruris muscles, which also surrounds the posterior neurovascular structures.

Establishment of an orthotopic transplantation tumor model of hepatocellular carcinoma in mice.

To improve the outcome of orthotopic transplantation in a mouse model, we used an absorbable gelatin sponge (AGS) in nude mice to establish an orthotopic implantation tumor model. MHCC-97L hepatocellular carcinoma (HCC) cells stably expressing the luciferase gene were injected into the subcutaneous region of nude mice. One week later, the ectopic tumors were harvested and transplanted into the left liver lobe of nude mice. The AGS was used to establish the nude mouse orthotopic implantation tumor model. The tumor suppressor gene, paired box gene 5 (PAX5), which is a tumor suppressor in HCC, was transfected into HCC cells to validate the model. Tumor growth was measured by bioluminescence imaging technology. Semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and histopathology were used to confirm the tumorigenicity of the implanted tumor from the MHCC-97L cell line. We successfully developed an orthotopic transplantation tumor model in nude mice with the use of an AGS. The success rate of tumor transplantation was improved from 60% in the control group to 100% in the experimental group using AGS. The detection of fluorescent signals showed that tumors grew in all live nude mice. The mice were divided into 3 groups: AGS-, AGS+/PAX5- and AGS+/PAX5+. Tumor size was significantly smaller in PAX5 transfected nude mice compared to control mice (P < 0.0001). These fluorescent signal results were consistent with observations made during surgery. Pathologic examination further confirmed that the tissues from the ectopic tumor were HCC. Results from RT-PCR proved that the HCC originated from MHCC-97L cells. Using an AGS is a convenient and efficient way of establishing an indirect orthotopic liver transplantation tumor model with a high success rate.

Evaluation of the rat tissue reaction to experimental new resin cement and mineral trioxide aggregate cement

ObjectivesNew resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials.Materials and MethodsSixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 µm thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05).ResultsIn specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk.ConclusionsIt was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.