994 resultados para Benign bone tumor
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We aimed to investigate the effects of an anti-tumor necrosis factor-α antibody (ATNF) on cartilage and subchondral bone in a rat model of osteoarthritis. Twenty-four rats were randomly divided into three groups: sham-operated group (n=8); anterior cruciate ligament transection (ACLT)+normal saline (NS) group (n=8); and ACLT+ATNF group (n=8). The rats in the ACLT+ATNF group received subcutaneous injections of ATNF (20 μg/kg) for 12 weeks, while those in the ACLT+NS group received NS at the same dose for 12 weeks. All rats were euthanized at 12 weeks after surgery and specimens from the affected knees were harvested. Hematoxylin and eosin staining, Masson's trichrome staining, and Mankin score assessment were carried out to evaluate the cartilage status and cartilage matrix degradation. Matrix metalloproteinase (MMP)-13 immunohistochemistry was performed to assess the cartilage molecular metabolism. Bone histomorphometry was used to observe the subchondral trabecular microstructure. Compared with the rats in the ACLT+NS group, histological and Mankin score analyses showed that ATNF treatment reduced the severity of the cartilage lesions and led to a lower Mankin score. Immunohistochemical and histomorphometric analyses revealed that ATNF treatment reduced the ACLT-induced destruction of the subchondral trabecular microstructure, and decreased MMP-13 expression. ATNF treatment may delay degradation of the extracellular matrix via a decrease in MMP-13 expression. ATNF treatment probably protects articular cartilage by improving the structure of the subchondral bone and reducing the degradation of the cartilage matrix.
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Keratocystic odontogenic tumor (KCOT) is a benign intraosseous neoplasm of odontogenic origin with high recurrence rate. To date, various conservative or aggressive management strategies have been suggested as a method of treatment. Decompression is a conservative method that has been used in the treatment of large odontogenic cysts. The present paper reports a case of KCOT located in the mandible and discusses the importance of its management using conservative methods. The authors present a case of a 38-year-old patient with a KCOT located in the right mandibular angle and ascending ramus, which was treated by decompression followed by enucleation and curettage. The lesion did not recur during a follow-up period of 3 years after surgery. Preserving important structures of the bone and soft tissue decompression is a method with low morbidity. In addition, according to the literature, decompression has a success rate at least as high as the one of most aggressive treatments.
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In this work we have:investigated the growth and differentiation of bone marrow stem cells in mice bearing Ehrlich ascites tumor-and treated with three dose-regimens of Dicyclopentadienyldichlorotitanium (IV) (DDCT). We also: studied the presence of colony stimulating factors In the serum of PDCT-treated animals as well-as the effects-of the drug on the survival of the tumor-bearing mice. The-results demonstrated that the myelosuppression developed in the tumor-bearing animals is prevented by the administration:of 1, 2 or 3 doses of 15 mg/kg DDCT. In the treatment with three doses, however, 23 % of the animals died. Moreover, DDCT treatment in normal animals resulted in increased numbers of CFU-GM. We observed the presence of stimulating factors in the serum of drug-treated animals which induced the growth and differentiation of bone marrow progenitor cells from normal animals in vitro. on the other hand, in vitro addition of the drug to these cultures had no effect. Thus, we conclude that the drug protects against the myelosuppression induced by the tumor and that this protection may be related to an indirect action of the drug. (C) 1998 International Society for Immunopharmacology. Published by Elsevier B.V. Ltd.
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Congenital epulis (CE) of the newborn is a rare benign soft tissue tumor that presents at birth. It occurs usually as a single mass with various sizes, although some multiple lesions have also been reported. The lesion is more common in female neonates and normally affects the maxillary alveolar ridge. Rare recurrence and no malignant alteration have also been reported. This condition may interfere with respiration, feeding or adequate closure of the mouth. A decisive diagnosis is made by histopathologic analysis as other newborn lesions can be incorrectly diagnosed as CE. This article presents a case report of a female infant who presented a fibrotic mass in the primary lateral incisor and canine region of the maxillary alveolar ridge. The lesion was not causing feeding or respiratory problems. After a watchful waiting procedure and no spontaneous regression, the lesion was excised under local anesthesia and confirmed by histopathologic analysis as CE.
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Background: The present study aims to evaluate the effects of orthodontic movement (OM) on the periodontal tissues of rats with ligature-induced periodontal disease. Methods: Eighty-eight rats were divided into four groups: 1) negative control (sham operated); 2) periodontal disease; 3) OM; and 4) periodontal disease followed by OM (OMP). Rats were sacrificed 3 hours or 1, 3, or 7 days after OM commencement. Bone volume fraction (BVF) and bone mineral density (BMD) were assessed in hemimaxillae by microcomputed tomography analysis. Expression of the proinflammatory cytokines interleukin (IL)-1β and tumor necrosis factor (TNF)-α were evaluated in gingival samples by quantitative polymerase chain reaction and enzyme-linked immunosorbent assay, and in the furcation region by immunohistochemistry analysis (IHC). Results: The OMP group had lower BVF and BMD levels compared to the other groups at day 7 (P <0.05). Maximum messenger ribonucleic acid expression of both cytokines was observed in the OMP group at day 1 (P <0.05). In the same period, all proteins were expressed in high levels for all test groups compared to the control group. The number of cells positive for IL-1β and TNF-α by IHC was highest in the OMP group at day 1, with progressive reduction thereafter. Conclusion: The results suggest that OM acts synergistically with periodontal disease in periodontal breakdown through upregulation of proinflammatory cytokines.
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Pós-graduação em Genética - IBILCE
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Background: Giant cell tumors of bone (GCTs) are common in the long bones, but rare in the craniofacial region, with only 1% of cases occurring in the latter. Clinical, radiological, and anatomical diagnosis of this locally aggressive disease, which occurs in response to trauma or neoplastic transformation, poses a major challenge in clinical practice. Methods: The present study describes a series of 4 cases and highlights the main features of the differential diagnosis and treatment of these lesions: GCT, giant cell reparative granuloma (GCRG), and the brown tumor of hyperparathyroidism. Results: GCT presents as a benign neoplasm, most typically affecting the knees, and rarely in the temporal and sphenoid bones. It is radiologically indistinguishable from GCRG due to its lytic, poorly defined appearance. The distinction can only be made microscopically, as the presence of multinucleated giant cells scattered throughout the stroma and the absence of a history of trauma favor a diagnosis of GCT. The brown tumor of hyperparathyroidism occurs with rapid, localized osteoclast activity secondary to the effects of increased parathyroid hormone (PTH) levels; parathyroid examination is indispensable. Conclusion: The diagnosis and treatment of these lesions poses a major challenge due to their similar clinical presentation and radiological appearance. Accurate diagnosis is essential for definition of appropriate management, as complete resection is the goal in GCT and GCRG to avoid recurrence, whereas the brown tumor often yields to treatment of the underlying hyperparathyroidism.
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Patienten, die an Osteosarkom leiden werden derzeit mit intravenös applizierten krebstherapeutischen Mitteln nach Tumorresektion behandelt, was oftmals mit schweren Nebenwirkungen und einem verzögerten Knochenheilungsprozess einhergeht. Darüber hinaus treten vermehrt Rezidive aufgrund von verbleibenden neoplastischen Zellen an der Tumorresektionsstelle auf. Erfolgreiche Knochenregeneration und die Kontrolle von den im Gewebe verbleibenden Krebszellen stellt eine Herausforderung für das Tissue Engineering nach Knochenverlust durch Tumorentfernung dar. In dieser Hinsicht scheint der Einsatz von Hydroxyapatit als Knochenersatzmaterial in Kombination mit Cyclodextrin als Medikamententräger, vielversprechend. Chemotherapeutika können an Biomaterial gebunden und direkt am Tumorbett über einen längeren Zeitraum freigesetzt werden, um verbliebene neoplastische Zellen zu eliminieren. Lokal applizierte Chemotherapie hat diverse Vorteile, einschließlich der direkten zytotoxischen Auswirkung auf lokale Zellen, sowie die Reduzierung schwerer Nebenwirkungen. Diese Studie wurde durchgeführt, um die Funktionsfähigkeit eines solchen Arzneimittelabgabesystems zu bewerten und um Strategien im Bereich des Tissue Engineerings zu entwickeln, die den Knochenheilungsprozess und im speziellen die Vaskularisierung fördern sollen. Die Ergebnisse zeigen, dass nicht nur Krebszellen von der chemotherapeutischen Behandlung betroffen sind. Primäre Endothelzellen wie zum Beispiel HUVEC zeigten eine hohe Sensibilität Cisplatin und Doxorubicin gegenüber. Beide Medikamente lösten in HUVEC ein tumor-unterdrückendes Signal durch die Hochregulation von p53 und p21 aus. Zudem scheint Hypoxie einen krebstherapeutischen Einfluss zu haben, da die Behandlung sensitiver HUVEC mit Hypoxie die Zellen vor Zytotoxizität schützte. Der chemo-protektive Effekt schien deutlich weniger auf Krebszelllinien zu wirken. Diese Resultate könnten eine mögliche chemotherapeutische Strategie darstellen, um den Effekt eines zielgerichteten Medikamenteneinsatzes auf Krebszellen zu verbessern unter gleichzeitiger Schonung gesunder Zellen. Eine erfolgreiche Integration eines Systems, das Arzneimittel abgibt, kombiniert mit einem Biomaterial zur Stabilisierung und Regeneration, könnte gesunden Endothelzellen die Möglichkeit bieten zu proliferieren und Blutgefäße zu bilden, während verbleibende Krebszellen eliminiert werden. Da der Prozess der Knochengeweberemodellierung mit einer starken Beeinträchtigung der Lebensqualität des Patienten einhergeht, ist die Beschleunigung des postoperativen Heilungsprozesses eines der Ziele des Tissue Engineerings. Die Bildung von Blutgefäßen ist unabdingbar für eine erfolgreiche Integration eines Knochentransplantats in das Gewebe. Daher ist ein umfangreich ausgebildetes Blutgefäßsystem für einen verbesserten Heilungsprozess während der klinischen Anwendung wünschenswert. Frühere Experimente zeigen, dass sich die Anwendung von Ko-Kulturen aus humanen primären Osteoblasten (pOB) und humanen outgrowth endothelial cells (OEC) im Hinblick auf die Bildung stabiler gefäßähnlicher Strukturen in vitro, die auch effizient in das mikrovaskuläre System in vivo integriert werden konnten, als erfolgreich erweisen. Dieser Ansatz könnte genutzt werden, um prä-vaskularisierte Konstrukte herzustellen, die den Knochenheilungsprozess nach der Implantation fördern. Zusätzlich repräsentiert das Ko-Kultursystem ein exzellentes in vitro Model, um Faktoren, welche stark in den Prozess der Knochenheilung und Angiogenese eingebunden sind, zu identifizieren und zu analysieren. Es ist bekannt, dass Makrophagen eine maßgebliche Rolle in der inflammatorisch-induzierten Angiogenese spielen. In diesem Zusammenhang hebt diese Studie den positiven Einfluss THP-1 abgeleiteter Makrophagen in Ko-Kultur mit pOB und OEC hervor. Die Ergebnisse zeigten, dass die Anwendung von Makrophagen als inflammatorischer Stimulus im bereits etablierten Ko-Kultursystem zu einer pro-angiogenen Aktivierung der OEC führte, was in einer signifikant erhöhten Bildung blutgefäßähnlicher Strukturen in vitro resultierte. Außerdem zeigte die Analyse von Faktoren, die in der durch Entzündung hervorgerufenen Angiogenese eine wichtige Rolle spielen, eine deutliche Hochregulation von VEGF, inflammatorischer Zytokine und Adhäsionsmoleküle, die letztlich zu einer verstärkten Vaskularisierung beitragen. Diese Resultate werden dem Einfluss von Makrophagen zugeschrieben und könnten zukünftig im Tissue Engineering eingesetzt werden, um den Heilungsprozess zu beschleunigen und damit die klinische Situation von Patienten zu verbessern. Darüber hinaus könnte die Kombination der auf Ko-Kulturen basierenden Ansätze für das Knochen Tissue Engineering mit einem biomaterial-basierenden Arzneimittelabgabesystem zum klinischen Einsatz kommen, der die Eliminierung verbliebener Krebszellen mit der Förderung der Knochenregeneration verbindet.
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Perineurioma is an uncommon, mostly benign, spindle-cell tumor of peripheral nerve sheath origin with a predilection for the soft tissues. Although increasing awareness points to the sites of involvement by perineurioma possibly being as ubiquitous as those frequented by schwannian tumors, only one intracerebral example has been described to date. We report on a surgically resected perineurioma of the falx cerebri in an 86-year-old woman. Preoperative imaging showed an enhancing extraaxial mass of 6 cm × 5.7 cm × 3.7 cm. Histologically, the tumor consisted of a proliferation of spindle cells interwoven by a lattice of basal lamina. Alongside a prevailing soft tissue perineurioma pattern, sclerosing and reticular areas were seen as well. Tumor cells coexpressed EMA and GLUT-1, and a minority immunoreacted for smooth muscle actin. Pericellular basal lamina was decorated with collagen type IV. No staining for S100 protein was detected. Mitotic activity was virtually absent, and the MIB1 labeling index averaged 2%. Ultrastructural examination revealed abundant pinocytotic vesicles within and conspicuous tight junctions between slender cytoplasmic processes which, in turn, were encased by discontinuous basal lamina. FISH analysis confirmed loss of at least part of one chromosome 22q. This observation calls attention to perineurioma as a novel item in the repertoire of low-grade meningial spindle cell neoplasms, in the differential diagnostic context of which it is apt to being misconstrued as either meningioma, solitary fibrous tumor, or neurofibroma. Confusion with the latter bears the risk of overgrading innocuous features of perineurioma as criteria for malignancy.
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Many surgeons treat giant cell tumor of bone (GCT) with intralesional curettage. Wide resection is reserved for extensive bone destruction where joint preservation is impossible or when expendable sites (eg, fibular head) are affected. Adjuvants such as polymethylmethacrylate and phenol have been recommended to reduce the risk of local recurrence after intralesional surgery. However, the best treatment of these tumors and risk factors for recurrence remain controversial.
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The descriptive term hybrid peripheral nerve sheath tumor refers to any neoplasm of the neurilemmal apparatus composed of more than one pathologically defined tumoral equivalent derived from its constituent cells. Within this uncommon nosological category, participation of granular cell tumor - a neoplasm of modified Schwann cells - has been reported only exceptionally. We describe a hitherto not documented variant composed of an organoid mixture of granular cell tumor and perineurioma with plexiform growth. A solitary subcutaneous nodule of 1.5 cm diameter was excised from the right ring finger of a 19-year-old female with no antecedents of neurofibromatosis or relevant trauma. Histology revealed a monotonous, yet cytologically dimorphic proliferation of classical granular cells intermingled with flattened, inconspicuous perineurial cells. Immunohistochemical double labeling detected expression of S100 protein in the former and of EMA and GLUT-1 in the latter. While the respective staining patterns for S100 protein and EMA or GLUT-1 tended to be mutually exclusive, a minority of cells exhibited transitional granular cell/perineurial immunophenotype. Electron microscopy permitted direct visualization of a plethora of lysosomes in the granular cell moiety, and of pinocytotic vesicles and tight junctions in perineurial cells. Intratumoral axons were not detected. Expanding intraneurally, the lesion showed discrete encapsulation by the local perineurium, and resulted in plexiform growth. The MIB-1 labeling index averaged 1%. We interpret our findings as supporting evidence for the dual cell lineage to have arisen through metaplasia, with the tumor's dynamics probably having been driven by the granular cell component.
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OBJECTIVE: The purpose of this study was to evaluate, in relation to intraoperative estimated blood loss (EBL), the effectiveness of preoperative transcatheter arterial embolization of hypervascular osseous metastatic lesions before orthopedic resection and stabilization. MATERIALS AND METHODS: Between June 1987 and November 2007, 22 patients underwent transcatheter arterial embolization of tumors of the long bone, hip, or vertebrae before resection and stabilization. Osseous metastatic lesions from renal cell carcinoma, malignant melanoma, leiomyosarcoma, and prostate cancer were embolized. All patients were treated with a coaxial catheter technique with polyvinyl alcohol (PVA) particles alone or a combination of PVA particles and coils. After embolization, each tumor was angiographically graded according to devascularization (grades 1-3) based on tumor blush after contrast injection into the main tumor-feeding arteries. RESULTS: In patients with complete devascularization (grade 1), mean EBL was calculated to be 1,119 mL, whereas in patients with partial embolization (grades 2 and 3) EBL was 1,788 mL and 2,500 mL. With respect to intraoperative EBL, no significant difference between devascularization grades was found (p > 0.05). Moderate correlation (r = 0.51, p = 0.019) was observed between intraoperative EBL and tumor size before embolization. Only low correlation (r = 0.44, p = 0.046) was found between intraoperative EBL and operating time. Major complications included transient palsy of the sciatic nerve and gluteal abscess in one patient. CONCLUSION: The results of this study support the concept that there is no statistically significant difference among amounts of intraoperative EBL with varying degrees of embolization.
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Allogeneic bone marrow transplantation (BMT) is known to induce a beneficial anti-tumor immune response called graft-versus-tumor (GVT) activity. However, GVT activity is closely associated with graft-versus-host disease (GVHD), a potentially fatal immune response against antigens on normal recipient tissues. The T-cell populations mediating these two processes are often overlapping, but studies have shown that some donor T-cells can be tumor-specific. Therefore, the goal of this study was to develop strategies for preferentially activating donor T-cells capable of mediating GVT activity but not GVHD. The three hypotheses tested were: (1) Pre-transplant immunization of BMT donors with a recipient-derived tumor cell vaccine will induce a relative increase in GVT activity as compared to GVHD. (2) Post-transplant tumor immunization of BMT recipients will enhance GVT activity without exacerbating GVHD. (3) Pre-transplant immunization of BMT donors against a tumor-specific antigen will enhance GVT activity without exacerbating GVHD. ^ To test the first two hypotheses, C3H.SW mice (MHC-matched donors) were immunized with a C57BL/6 (recipient)-derived tumor cell vaccine (leukemia or fibrosarcoma) prior to BMT, or recipients were immunized starting one month after BMT. Both donor and recipient immunization led to a significant increase in GVT activity (enhanced recipient survival and decreased tumor growth). However, donor immunization also increased fatal GVHD, which was at least partially due to activation of alloreactive T-cells recognizing the immunodominant minor histocompatibility antigen B6dom1. GVT immunity following recipient immunization was not associated with an exacerbation of GVHD or a response to B6dom1. ^ To test the third hypothesis, influenza nucleoprotein (NP) was used as a model tumor antigen. C3H.SW donors were immunized against NP prior to BMT, which led to a significant increase in GVT activity. Although recipients were not completely protected against growth of antigen loss variant tumors, there was no increase in GVHD. ^ In conclusion, (1) immunization of allogeneic BMT donors with a recipient-derived tumor cell vaccine substantially increases GVT activity but also exacerbates GVHD, (2) post-transplant tumor immunization of allogeneic BMT recipients significantly increases GVT activity and survival without exacerbating GVHD, and (3) immunization of allogeneic BMT donors against a tumor-specific antigen significantly enhances GVT activity without exacerbating GVHD. ^
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First described in 1768, the Pott's puffy tumor is a subperiosteal abscess associated with frontal bone osteomyelitis, resulting from trauma or frontal sinusitis. The classic clinical presentation consists of purulent rhinorrhea, fever, headache, and frontal swelling. The diagnosis is confirmed by CT scan and treatment requires intravenous antibiotics, analgesia, and surgical intervention. Early diagnosis and aggressive medical and surgical approach are essential for a good outcome. It rare and the early diagnosis is important; we describe the case of a 14-year-old adolescent with Pott's puffy tumor who was initially treated inadequately, evolving with extensive frontoparietal abscess. The patient underwent surgical treatment with endoscopic endonasal and external approaches combined. Intravenous antibiotics were prescribed for a prolonged time, with good outcome and remission of the complaints.
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Purpose: To evaluate the expression of NF-kappa B pathway genes in total bone marrow samples obtained from MM at diagnosis using real-time quantitative PCR and to evaluate its possible correlation with disease clinical features and survival. Material and methods: Expression of eight genes related to NF-kappa B pathway (NFKB1, IKB, RANK, RANKL, OPG, IL6, VCAM1 and ICAM1) were studied in 53 bone marrow samples from newly diagnosed MM patients and in seven normal controls, using the Taqman system. Genes were considered overexpressed when tumor expression level was at least four times higher than that observed in normal samples. Results: The percentages of overexpression of the eight genes were: NFKB1 0%, IKB 22.6%, RANK 15.1%, RANKL 31.3%, OPG 7.5%, IL6 39.6%, VCAM1 10% and ICAM1 26%. We found association between IL6 expression level and International Staging System (ISS) (p = 0.01), meaning that MM patients with high ISS scores have more chance of overexpression of IL6. The mean value of ICAM1 relative expression was also associated with the ISS score (p = 0.02). Regarding OS, cases with IL6 overexpression present worse evolution than cases with IL6 normal expression (p = 0.04). Conclusion: We demonstrated that total bone marrow aspirates can be used as a source of material for gene expression studies in MM. In this context, we confirmed that IL6 overexpression was significantly associated with worse survival and we described that it is associated with high ISS scores. Also, ICAM1 was overexpressed in 26% of cases and its level was associated with ISS scores.