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Find video protocols related to scientific articles indexed in Pubmed.
Fifteen-year survivor of renal cell carcinoma after metastasectomies for multiple bone metastases.
Orthopedics
PUBLISHED: 11-09-2013
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This article describes a patient with multiple metastases from renal cell carcinoma who survived and maintained an ambulatory status for 15 years with no recurrence in the spine after en bloc resection of solitary spinal metastasis. Skeletal metastasis from renal cell carcinoma is common, second only to lung metastasis. Surgery plays an important role in the treatment of the metastasis because of its resistance to chemotherapy and radiotherapy. A 60-year-old man had T1N2M1 renal cell carcinoma in the right kidney and synchronous bone metastases at T12 vertebral body and the right humerus. The patient underwent right nephrectomy and en bloc resection of T12 metastasis at the same time using a retroperitoneal approach. He also underwent curetted total excision of metastasis in the right humerus. He underwent radiotherapy and an additional 7 tumor excision surgeries in the right humerus due to repeated tumor recurrences and a pulmonary metastasectomy in the right lung. Thirteen years after initial surgery, he underwent right forequarter amputation due to tumor recurrence and surgical site infection. Fifteen years after initial surgery, he is still alive with no evidence of disease. He has been ambulatory with no tumor recurrence in the spine for 15 years. En bloc resection of solitary spinal metastasis allowed the patient to be ambulatory without recurrence. This contrasts with curetted total excision of bone metastasis in the humerus that resulted in repeated recurrences and surgeries and loss of the arm.
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Patient and family satisfaction with en bloc total resection as a treatment for solitary spinal metastasis.
Orthopedics
PUBLISHED: 11-09-2013
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Many studies have evaluated patient satisfaction surgeries for primary cancers. No studies have evaluated patient satisfaction in metastasectomies. The authors examined patient and family satisfaction with en bloc total resection of solitary spinal metastases and evaluated the factors that correlated with dissatisfaction. From 1998 to 2010, total en bloc spondylectomy (TES) was performed in 110 patients with solitary spinal metastases at the authors institution. Questionnaires were sent by mail to 110 patients and their families in January 2012. Questionnaire included a subjective assessment of the results of surgery and the following questions: (1) Would you have the surgery again if you were returned to your presurgery status? and (2) Do you feel that you are a patient without cancer? To identify factors for dissatisfaction with the outcomes of TES, univariate and multivariate analyses were performed. Questionnaires were successfully delivered to 104 patients and their families. Responses were collected from 47 patients and 61 family members. Forty-five patients were very satisfied or satisfied with the outcomes of TES, and the other 2 were neutral. Fifty-four family members were very satisfied or satisfied, 5 were neutral, and 2 were dissatisfied. Forty-five patients indicated they would have the surgeries again. Thirteen patients indicated that they felt like patients without cancer. In multivariate analysis, patient death less than 2 years postoperatively and major postoperative complications were associated significantly with dissatisfaction.
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Primer dosing of S. typhimurium A1-R potentiates tumor-targeting and efficacy in immunocompetent mice.
Anticancer Res.
PUBLISHED: 06-01-2013
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We developed the tumor-targeting strain Salmonella typhimuium A1-R (A1-R) and have shown it to be active against a number of tumor types in nude mice. However, in immunocompetent mice, dosing of A1-R has to be adjusted to avoid toxicity. In the present study, we developed a strategy to maximize efficacy and minimize toxicity for A1-R tumor-targeting in immunocompetent mice implanted with the Lewis lung carcinoma. A small primer dose of A1-R was first administered (1×10(6) colony forming unit [cfu] i.v.) followed by a high dose (1×10(7) cfu i.v.) four hours later. The primer-dose strategy resulted in smaller tumors and no observable side-effects compared to treatment with high-dose-alone. The serum level of tumor necrosis factor (TNF-?) was elevated in the mice treated with primer dose compared to mice only given the high dose. Tumor vessel destruction was enhanced by primer dosing of A1-R in immuno-competent transgenic mice expressing the nestin-driven green fluorescent protein, which is selectively expressed in nascent blood vessels. The primer-dose may activate TNF-? and other cytokines in the mouse, necessary for invasion of the tumor by the bacteria, as well as enhance tumor vessel destruction, thereby allowing a subsequent therapeutic dose to be effective and safe. The results of the present study suggest effective future clinical strategies of bacterial treatment of cancer.
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More Than 10-Year Follow-Up After Total En Bloc Spondylectomy for Spinal Tumors.
Ann. Surg. Oncol.
PUBLISHED: 05-01-2013
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There are many reports of en bloc resection for spinal tumors. However, no studies have evaluated the clinical outcomes with follow-up exceeding 10 years after surgery.
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Assessment of quality of life after surgery for spinal metastases: position statement of the global spine tumour study group.
World Neurosurg
PUBLISHED: 02-02-2013
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To review suitable measures of patient-assessed outcome of surgery for spinal metastases, and suggest the Health-Related Quality of Life measures that are useful and practical for this group of patients.
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Comparison of cancer-cell seeding, viability and deformation in the lung, muscle and liver, visualized by subcellular real-time imaging in the live mouse.
Anticancer Res.
PUBLISHED: 11-24-2011
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The comparison of cancer cell seeding, deformation and viability in the lung, muscle and liver of nude mice in real-time is reported here. The mice were intubated to support ventilation with positive end-respiratory pressure (PEEP) for imaging on the lung. Human fibrosarcoma cells with green fluorescent protein (GFP) in the nucleus and red fluorescent protein (RFP) in the cytoplasm (dual-color HT-1080 cells) were injected into the tail vein for lung imaging, the portal vein for liver imaging or the abdominal aorta for muscle imaging which was performed with an Olympus OV100 Small Animal Imaging System. The length of the cytoplasm and nuclei in 20 seeded cancer cells were measured. A large number of cells initially arrested in the lung capillaries and many cells formed aggregates. The cell number decreased rapidly at 6 and 24 h. There was no significant difference in cancer cell survival when immunocompetent C57BL/6 mice were used in place of the nude mice, suggesting that T cell reaction is not very important in the first 24 h after seeding of cancer cells in the lung. In the lung and liver, little cancer cell deformation occurred. In contrast in the muscle, the cytoplasm and nuclei of the seeded cells were highly deformed and many fragmented cells were observed. The rate of cancer cell death was highest in the lung and lowest in the muscle. In each organ, single disseminated cells tended to die earlier than aggregated cells. The results of this study suggest that the early steps of metastasis are different in the lung, liver and muscle.
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Outcomes of fusion surgery for ossification of the posterior longitudinal ligament of the thoracic spine: a multicenter retrospective survey: clinical article.
J Neurosurg Spine
PUBLISHED: 07-08-2011
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The aim of this study was to evaluate the outcomes of fusion surgery in patients with ossification of the posterior longitudinal ligament in the thoracic spine (T-OPLL) and to identify factors significantly related to surgical outcomes.
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Spinal instability neoplastic score: an analysis of reliability and validity from the spine oncology study group.
J. Clin. Oncol.
PUBLISHED: 06-27-2011
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Standardized indications for treatment of tumor-related spinal instability are hampered by the lack of a valid and reliable classification system. The objective of this study was to determine the interobserver reliability, intraobserver reliability, and predictive validity of the Spinal Instability Neoplastic Score (SINS).
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Activation of tumor suppressor protein PTEN and induction of apoptosis are involved in cAMP-mediated inhibition of cell number in B92 glial cells.
Neurosci. Lett.
PUBLISHED: 03-09-2011
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During brain development, cAMP induces morphological changes and inhibits growth effects in several cell types. However, the molecular mechanisms underlying the growth inhibition remain unknown. Tumor suppressor protein phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a lipid phosphatase that inhibits the phosphoinositide 3-kinase (PI3K) pathway. The phosphorylation of Akt, which is one of the key molecules downstream of PI3K, inhibits apoptosis. In this study, we investigated the role of PTEN in cAMP-mediated growth inhibition. B92 rat glial cells were treated with 2 different cAMP stimulatory agents, a phosphodiesterase (PDE) inhibitor and a ?-adrenoceptor agonist. Both cAMP stimulatory agents induced marked morphological changes in the cells, decreased cell number, decreased Akt phosphorylation, activated PTEN, cleaved caspase-3, and induced the condensation and fragmentation of nuclei. These results indicate that the cAMP stimulatory agents induced apoptosis. Protein phosphatase inhibitor prevented cAMP-induced dephosphorylation of PTEN and Akt. In addition, cAMP analogs and Epac-selective agonists affected PTEN and Akt activities. These results suggested that cAMP-induced apoptosis may be mediated by PTEN activation and Akt inhibition through protein phosphatase in B92 cells. Our results provide new insight into the role of PTEN in cAMP-induced apoptosis in glial cells.
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The route of metastatic vertebral tumors extending to the adjacent vertebral body: a histological study.
J Orthop Sci
PUBLISHED: 03-02-2011
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Each vertebra can be regarded as a compartment surrounded by several anatomically characterized barriers. However, in some cases tumors extend beyond these barriers. The route of vertical extension to the adjacent vertebrae is unclear. The extent of vertical extension of a metastatic spinal tumor is important in making the preoperative decision regarding the cranio-caudal surgical margin. The objective of this study was to investigate the route of vertical extension of metastatic vertebral tumors.
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Potentiation of the antitumor effect of calcium phosphate cement containing anticancer drug and caffeine on rat osteosarcoma.
J Orthop Sci
PUBLISHED: 03-01-2011
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Several reports suggest diffusion of anticancer agents from bone cement may suppress tumor growth. New drug delivery systems have been developed that incorporate anticancer drugs into calcium phosphate cement (CPC) to maintain high concentrations of anticancer drugs at local sites. We investigated whether CPC implants containing anticancer drugs and caffeine, which enhance the cytocidal effect of anticancer drugs, would enhance their antitumor effects on rat osteosarcomas (SOSN2 cells).
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Total en bloc spondylectomy for spinal metastases in thyroid carcinoma.
J Neurosurg Spine
PUBLISHED: 12-24-2010
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Thyroid carcinoma generally has a favorable prognosis, and patients rarely present with distant metastases. Authors of several studies have proposed piecemeal resection for spinal metastases in thyroid carcinoma; however, few have analyzed the impact of local curative surgery such as total en bloc spondylectomy (TES) for thyroid carcinoma. The purposes of the present study are to determine the strategy of surgical treatment for spinal metastases of thyroid carcinoma and to evaluate the surgical results of and the prognosis associated with TES.
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Venous thromboembolism after spine surgery: changes of the fibrin monomer complex and D-dimer level during the perioperative period.
J Neurosurg Spine
PUBLISHED: 11-03-2010
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The goal of this study was to determine the incidence of deep venous thrombosis (DVT) and pulmonary embolism (PE) after spine surgery. Another purpose was to clarify the rapid changes of the fibrin monomer complex (FMC) and D-dimer levels during the perioperative period of spine surgery for early diagnosis of venous thromboembolism (VTE).
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Does interruption of the artery of Adamkiewicz during total en bloc spondylectomy affect neurologic function?
Spine
PUBLISHED: 10-21-2010
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A retrospective review of patients with interruption of the artery of Adamkiewicz during total en bloc spondylectomy (TES).
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Total en bloc spondylectomy for lung cancer metastasis to the spine.
J Neurosurg Spine
PUBLISHED: 10-05-2010
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The prognosis in patients with a distant spinal metastasis from the lung is dismal. The role of radical surgery in such cases has been questioned because of the excessive morbidity, blood loss, and operative time as well as the tumors extreme malignancy. The purpose of this study was to evaluate the surgical results and the prognosis associated with radical surgery for lung cancer metastasis to the spine in carefully selected patients and to clarify whether there is an indication for radical surgery such as total en bloc spondylectomy (TES) in lung cancer metastasis.
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Multi-level total en bloc spondylectomy for solitary lumbar metastasis of myxoid liposarcoma.
Orthopedics
PUBLISHED: 09-02-2010
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This article reports a case of solitary lumbar metastasis of myxoid liposarcoma treated by multi-level total en bloc spondylectomy. Myxoid liposarcoma has a predisposition to initial metastasis at an extrapulmonary site including bone. However a bone scan and FDG-PET, which are generally used for a whole-body screening of metastasis, are not sensitive to bone metastasis from myxoid liposarcoma. These situations make it difficult to achieve curative resection of a bone metastasis, especially in the spine. The patient was a 54-year-old man who had an intralesional excision of soft tissue tumor in the right thigh. He had an additional expansive excision due to the histological diagnosis of myxoid liposarcoma at the initial surgery. Four years postoperatively, L3 metastasis expanding to the adjacent vertebrae was detected using magnetic resonance imaging. Plain radiographs and computed tomography showed no evidence of the tumor involving the lumbar spine. A bone scan was false-negative although FDG-PET showed mild uptake. There was no other metastasis on the further examination. Multi-level total en bloc spondylectomy was performed using a combined posterior-anterior approach. The lumbar nerves were dissected and preserved. The vertebral bodies of L2, 3 and the upper half of L4, which had been invaded by the tumor, were removed en bloc using an anterolateral extraperitoneal approach. He had no local recurrence or further metastasis until he died of ischemic cardiac disease 14 months postoperatively.
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Long-working-distance fluorescence microscope with high-numerical-aperture objectives for variable-magnification imaging in live mice from macro- to subcellular.
J Biomed Opt
PUBLISHED: 08-09-2010
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We demonstrate the development of a long-working-distance fluorescence microscope with high-numerical-aperture objectives for variable-magnification imaging in live mice from macro- to subcellular. To observe cytoplasmic and nuclear dynamics of cancer cells in the living mouse, 143B human osteosarcoma cells are labeled with green fluorescent protein in the nucleus and red fluorescent protein in the cytoplasm. These dual-color cells are injected by a vascular route in an abdominal skin flap in nude mice. The mice are then imaged with the Olympus MVX10 macroview fluorescence microscope. With the MVX10, the nuclear and cytoplasmic behavior of cancer cells trafficking in blood vessels of live mice is observed. We also image lung metastases in live mice from the macro- to the subcellular level by opening the chest wall and imaging the exposed lung in live mice. Injected splenocytes, expressing cyan fluorescent protein, could also be imaged on the lung of live mice. We demonstrate that the MVX10 microscope offers the possibility of full-range in vivo fluorescence imaging from macro- to subcellular and should enable widespread use of powerful imaging technologies enabled by genetic reporters and other fluorophores.
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Polyneuropathy caused by cobalt-chromium metallosis after total hip replacement.
Muscle Nerve
PUBLISHED: 06-15-2010
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Although metal intoxication after arthroplasty causes various symptoms, polyneuropathy has never been the focus of clinical investigation. We report the case of a 56-year-old woman with metal neuropathy. She had metallosis after hip arthroplasty with a cobalt-chromium alloy prosthesis. She developed progressive sensory disturbance, hearing loss, and hypothyroidism. Sural nerve biopsy indicated axonopathy. After exchange arthroplasty, blood levels of cobalt and chromium decreased, and her symptoms improved. Cobalt or chromium can cause axonopathy.
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UV light killing efficacy of fluorescent protein-expressing cancer cells in vitro and in vivo.
J. Cell. Biochem.
PUBLISHED: 05-28-2010
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We investigated the cell-killing efficacy of UV light on cancer cells expressing GFP in the nucleus and RFP in the cytoplasm (dual-color cells). After exposure to various doses of UVA, UVB, or UVC, apoptotic and viable cells were quantitated under fluorescence microscopy using dual-color 143B human osteosarcoma cells, HT-1080 human fibrosarcoma cells, Lewis lung carcinoma (LLC), and XPA-1 human pancreatic cancer cells in vitro. UV-induced cancer cell death was wave-length and dose dependent, as well as cell-line dependent. After UVA exposure, most cells were viable even when the UV dose was increased up to 200 J/m(2). With UVB irradiation, cell death was observed with irradiation at 50 J/m(2). For UVC, as little as 25 J/m(2) UVC irradiation killed approximately 70% of the 143B dual-color cells. This dose of UVB or UVA had almost no effect on the cancer cells. UV-induced cancer cell death varied among the cell lines. Cell death began about 4 h after irradiation and continued until 10 h after irradiation. UVC exposure also suppressed cancer cell growth in nude mice in a model of minimal residual cancer (MRC). No apparent side effects of UVC exposure were observed. This study opens up the possibility of UVC treatment for MRC after surgical resection.
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A synthetic compound that potentiates bone morphogenetic protein-2-induced transdifferentiation of myoblasts into the osteoblastic phenotype.
Mol. Cell. Biochem.
PUBLISHED: 05-24-2010
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There is an urgent need to develop methods that lower costs of using recombinant human bone morphogenetic proteins (BMPs) to promote bone induction. In this study, we demonstrate the osteogenic effect of a low-molecular weight compound, SVAK-12, that potentiated the effects of BMP-2 in inducing transdifferentiation of C2C12 myoblasts into the osteoblastic phenotype. Here, we report a specific compound, SVAK-12, which was selected based on in silico screenings of small-molecule databases using the homology modeled interaction motif of Smurf1-WW2 domain. The enhancement of BMP-2 activity by SVAK-12 was characterized by evaluating a BMP-specific reporter activity and by monitoring the BMP-2-induced expression of mRNA for osteocalcin and alkaline phosphatase (ALP), which are widely accepted marker genes of osteoblast differentiation. Finally, we confirmed these results by also measuring the enhancement of BMP-2-induced activity of ALP. Smurf1 is an E3 ligase that targets osteogenic Smads for ubiquitin-mediated proteasomal degradation. Smurf1 is an interesting potential target to enhance bone formation based on the positive effects on bone of proteins that block Smurf1-binding to Smad targets or in Smurf1-/- knockout mice. Since Smads bind Smurf1 via its WW2 domain, we performed in silico screening to identify compounds that might interact with the Smurf1-WW2 domain. We recently reported the activity of a compound, SVAK-3. However, SVAK-3, while exhibiting BMP-potentiating activity, was not stable and thus warranted a new search for a more stable and efficacious compound among a selected group of candidates. In addition to being more stable, SVAK-12 exhibited a dose-dependent activity in inducing osteoblastic differentiation of myoblastic C2C12 cells even when multiple markers of the osteoblastic phenotype were parallelly monitored.
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Effect of near-infrared light-emitting diodes on nerve regeneration.
J Orthop Sci
PUBLISHED: 04-01-2010
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Photobiomodulation by red to near-infrared light-emitting diodes (LEDs) has been reported to accelerate wound healing, attenuate degeneration of an injured optic nerve, and promote tissue growth. The purpose of this study was to investigate the effect of LEDs on nerve regeneration. A histological study as well as a measurement of antioxidation levels in the nerve regeneration chamber fluid was performed.
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Perioperative complications and prognosis for elderly patients with spinal metastases treated by surgical strategy.
Orthopedics
PUBLISHED: 03-31-2010
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The rapidly aging population and improved long-term survival due to advancement of cancer treatment have expanded the role of surgical treatment in elderly patients with metastatic spinal disease. The purpose of this study was to evaluate in elderly patients the perioperative complications and prognosis for metastatic spinal disease. Thirty-two elderly patients (>70 years) who underwent surgical treatment based on Tomitas surgical strategy for spinal metastasis since 1999 were retrospectively reviewed. Mean survival time of 15 patients with 2 to 4 points in surgical strategy was 23.6 months; of 10 patients with 5 to 7 points was 15.2 months; and of 7 patients with 8 to 10 points was 5.2 months. In 5 elderly patients (15.6%), the appropriate surgical choice based on the surgical strategy was not possible due to their preoperative conditions. Perioperative complications encountered were respiratory in 6 patients (18.8%), cardiovascular in 3 (9.4%), and delirium in 4 (12.5%). In the nonelderly 161 patients, respiratory complications occurred in 4 patients (2.5%), cardiovascular in 1 (0.6%), and delirium in 2 (1.2%). Respiratory complications and delirium occurred at a significantly higher frequency in the elderly group. Even for elderly patients, the postoperative prognosis could be predicted by the surgical strategy. However, the optimal surgical procedure may deviate from that predicted by the surgical strategy due to their preoperative conditions and an increased risk for perioperative complications. Despite the increased potential for complications, more radical procedures, such as total en bloc spondylectomy, should not be avoided solely due to advanced patient age.
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Neurological function after total en bloc spondylectomy for thoracic spinal tumors.
J Neurosurg Spine
PUBLISHED: 03-03-2010
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Total en bloc spondylectomy (TES) for thoracic spinal tumors may in theory produce neurological dysfunction as a result of ischemic or mechanical damage to the spinal cord. Potential insults include preoperative embolization at 3 levels, intraoperative ligation of segmental arteries, nerve root ligation, and circumferential dural dissection. The purpose of this study was to assess neurological function after thoracic TES.
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Malunion of fractures of the proximal phalangeal neck in children.
Scand J Plast Reconstr Surg Hand Surg
PUBLISHED: 02-18-2010
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We report three cases of malunion after fractures of the proximal phalangeal neck in children. A 12-year-old boy and a 7-year-old girl had malunited fractures with dorsal and ulnar deviation of their fingers. Several years later remodeling had been achieved well for dorsal deviation but little for the ulnar deviation in each case. A 10-year-old boy had a similar malunited fracture with dorsal and ulnar deviation of his finger. The proximal bony spike, which protruded to the volar side, collided with the middle phalanx during flexion of the proximal interphalangeal (PIP) joint, so we shaved it. One year after operation, flexion of the PIP joint had improved. In cases of these malunited fractures in children, remodeling is considered possible for dorsal deviation but difficult for ulnar deviation. Surgical shaving of the protruding bone should be considered.
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Activation of the extracellular signal-regulated kinase signal pathway by light emitting diode irradiation.
Lasers Med Sci
PUBLISHED: 02-17-2010
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Irradiation by light emitting diode (LED) promotes fibroblast proliferation and wound healing. However, its mechanism is still unknown. The purpose of this study was to clarify the mechanism of fibroblast proliferation by LED irradiation. Cultured NIH3T3 fibroblasts from normal mice were irradiated by LED with a center wavelength of 627 nm. LED irradiation was performed with an energy density of 4 J/cm(2), at subculture and 24 h later. The expression of several growth factors and their receptors was analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR): platelet-derived growth factor (PDGF)-A, PDGF-B, and PDGF-C, transforming growth factor-beta (TGF-beta), basic fibroblast growth factor (bFGF), PDGF-alpha receptor, and TGF-beta receptor. Then, the activation of the extracellular signal-regulated kinase (ERK) pathway was examined by Western blotting with and without the PDGF receptor inhibitor. LED irradiation induced cell growth of NIH3T3 fibroblasts. The expression of PDGF-C had significantly increased in the irradiated group (P < 0.01). Although strong activation of the ERK pathway was observed in the irradiated group, its activation was completely suppressed by the PDGF receptor inhibitor. We concluded that LED irradiation promotes fibroblast proliferation by increasing autocrine production of PDGF-C and activating the ERK pathway through phosphorylation of the PDGF receptor.
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Facilitated tendon-bone healing by local delivery of recombinant hepatocyte growth factor in rabbits.
Arthroscopy
PUBLISHED: 02-02-2010
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This study was performed to evaluate the therapeutic effect of hepatocyte growth factor (HGF) on tendon-bone healing in a rabbit model.
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Interleukin-6 upregulates the expression of PMP22 in cultured rat Schwann cells via a JAK2-dependent pathway.
Neurosci. Lett.
PUBLISHED: 01-26-2010
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The interleukin-6 (IL-6) family of cytokines is thought to be involved in the development and regeneration of peripheral nerves; however, their roles in myelination remain unclear. In this study, we examined the effects of IL-6 on the expression of genes for compact myelin proteins using Schwann cell cultures prepared by multiple explantation of adult rat sciatic nerves. In semi-quantitative reverse transcription-polymerase chain reaction analysis, stimulation of Schwann cells with IL-6 significantly increased the mRNA level of peripheral myelin protein 22 (PMP22), but not those of myelin protein zero and myelin basic protein. The increase in PMP22 mRNA was markedly suppressed by AG490, a Janus kinase 2 (JAK2) inhibitor, but not significantly by PD098059, a mitogen-activated protein kinase inhibitor. Immunocytochemical staining revealed that IL-6 enhanced immunoreactivities for the phosphorylated forms of both JAK2 and signal transducer and activator of transcription 3 (STAT3), as well as that for PMP22. These results indicate that IL-6 can enhance PMP22 production in Schwann cells via a JAK2-dependent pathway by probably activating STAT3 and thus may contribute to myelination.
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Pedicle frozen autograft reconstruction in malignant bone tumors.
J Orthop Sci
PUBLISHED: 01-21-2010
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Standardizing limb salvage surgery for malignant bone tumors should result in improved limb function after tumor excision and reconstruction. Recently, we developed and clinically applied a method of biological reconstruction using tumor-bearing autografts treated with liquid nitrogen. We report this newly modified technique using pedicle frozen autografts to save the continuity of anatomical structures.
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Surgical management of aggressive vertebral hemangiomas causing spinal cord compression: long-term clinical follow-up of five cases.
J Orthop Sci
PUBLISHED: 01-03-2010
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Aggressive vertebral hemangiomas causing spinal compression are rare, and there is controversy with regard to treatment. The purpose of this study was to evaluate the clinical results of patients with aggressive vertebral hemangiomas at a mean follow-up of more than 10 years after total excision and discuss the treatment options for the tumors.
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Decompression, correction, and interbody fusion for lumbar burst fractures using a single posterior approach.
Orthopedics
PUBLISHED: 10-15-2009
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Burst fractures of the lumbar spine with instability or severe kyphosis are best served by surgical treatment. The question as to how these fractures should be approached and stabilized (anteriorly, posteriorly, or combined anteroposteriorly) is controversial. We performed decompression, correction, and interbody fusion using a single posterior approach for Denis type B or C lumbar burst fractures with severe kyphosis. The operative technique is as follows: after partial laminectomy, the bone fragment, which had migrated into the spinal canal, is impacted into the posterior wall of the vertebral body. After curetting the injured disk, bone chips and adapted lamina are inserted into the disk space for anterior support. Five Denis type B or C burst fractures demanding >20 degrees kyphosis correction were treated by this procedure. Mean follow-up was 41 months. We evaluated neurologic assessment and localized kyphotic angle. The neurologic function of all 5 patients improved by at least 1 grade, as measured by the Frankel grading scale. Mean values of localized kyphosis improved from a mean 23.0. before surgery to -3.0 degrees after surgery. At follow-up examination, average regional kyphosis was -2.4 degrees . No implant failure was observed at follow-up. Bony fusion was achieved in all patients. The advantages of this operative procedure are it is safe for the neural structures and complete spinal canal decompression and kyphosis correction are achieved, while providing anterior support and posterior stabilization.
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Effect of polarized light emitting diode irradiation on wound healing.
J Trauma
PUBLISHED: 08-15-2009
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We propose a new phototherapy using polarized light from light emitting diode (LED). The purpose of this study is to clarify the effect of polarized LED irradiation on wound healing.
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Use of bisphosphonates for the treatment of stress fractures in athletes.
Knee Surg Sports Traumatol Arthrosc
PUBLISHED: 08-01-2009
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A literature review was performed to investigate the potential role of bisphosphonates for the treatment of stress fractures in athletes. Given the inhibitory action on osteoclast-mediated bone resorption, short-term suppression of bone remodeling using bisphosphonates could potentially treat stress fractures and prevent stress fractures from becoming regular fractures. To date, while there are some animal studies showing the scientific basis of bisphosphonates on stress fractures, there is still no conclusive evidence to prove any effect of bisphosphonates on stress fracture healing in humans. Further well-designed clinical trials should be carried out to establish their usefulness and safety. Until the results are available, it is prudent to limit the use of bisphosphonates for the treatment of stress fractures.
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Cervicothoracic giant cell tumor expanding into the superior mediastinum: total excision by combined anterior-posterior approach.
Orthopedics
PUBLISHED: 07-29-2009
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This article describes a case of cervicothoracic giant cell tumor expanding into the superior mediastinum treated by total spondylectomy. A 42-year-old-man presented with back pain and paraparesis. Magnetic resonance imaging revealed the collapse of the T2 vertebral body. The spinal cord was severely compressed by the tumor mass. The tumor had spread from T2 to the mediastinum, so that the tumor was in contact with many vital structures. To resect the tumor completely, total spondylectomy from T1 to T3 was performed through a combined anterior-posterior approach. The tumor was dissected from the vital structures using an anterior low cervical approach and splitting one-third of the sternum. En bloc vertebral resection from Th1 to Th3, including the tumor pseudocapsule, was possible through a posterior approach. The tumor around the nerve roots or dura was resected piece by piece since it was possible to separate the capsulated tumor from the dura. Splitting one-third of the sternum allowed separation of the tumor from the anterior vital structures, under direct vision. This allowed en bloc vertebral resection of the tumor that had spread to the mediastinum from T2 and in the craniocaudal direction from T1 to T3. Although giant cell tumor is benign, it can be locally aggressive. Complete excision of a giant cell tumor is the best treatment option even for the cervicothoracic spine, to protect the vital structures or neural function.
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In vivo gene transfer between interacting human osteosarcoma cell lines is associated with acquisition of enhanced metastatic potential.
J. Cell. Biochem.
PUBLISHED: 07-23-2009
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We report here in vivo gene transfer between cancer cells is associated with acquisition of high metastatic behavior. The 143B-GFP cell line with high metastatic potential and the MNNG/HOS-RFP cell line with low metastatic potential, both derived from the TE85 human osteosarcoma cell line, were either co-transplanted or transplanted alone in the tibia in nude mice. Upon mixed transplantation of the two differently labeled sublines, resulting metastatic colonies are single colored either red or green, thereby demonstrating their clonality and enabling facile color-coded quantification. When MNNG/HOS-RFP and 143B-GFP were co-transplanted in the tibia, the number of lung metastases of MNNG/HOS-RFP increased eight-fold compared to MNNG/HOS-RFP transplanted alone (P < 0.01). In contrast, no enhancement of MNNG/HOS-RFP metastases occurred when MNNG/HOS-RFP and 143B-GFP were transplanted separately in the right and left tibiae, respectively. This result suggests that the presence of 143B-GFP increased the metastatic potential of MNNG/HOS-RFP within the mixed tumor. We observed transfer of the Ki-ras gene from 143B-GFP to MNNG/HOS-RFP after they were co-implanted suggesting the Ki-ras played a role in increasing the metastatic potential of MNNG/HOS-RFP in the presence of 143B-GFP. These data suggest the possible role of in vivo gene transfer in enhancing the metastatic potential of cancer cells. The data also further demonstrated the power of color-coded imaging to visualize cancer-cell/cancer-cell interactions in vivo.
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Efficacy of a genetically-modified Salmonella typhimurium in an orthotopic human pancreatic cancer in nude mice.
Anticancer Res.
PUBLISHED: 06-17-2009
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We report here a tumor-targeting strategy for pancreatic cancer using a modified auxotrophic strain of Salmonella typhimurium. The genetically-modified strain of S. typhimurium requires the amino acids arginine and leucine. These mutations preclude growth in normal tissue but do not reduce bacterial virulence in tumor cells. The tumor-targeting strain of S. typhimurium, termed A1-R and expressing green fluorescent protein (GFP), was administered to an orthotopic human pancreatic tumor expressing red fluorescent protein (RFP) in nude mice. After 7 days of treatment, the pancreatic cancer had regressed without the need of chemotherapy or any other treatment. This new strategy demonstrates the clinical potential of bacterial targeting for pancreatic cancer.
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Recapping T-saw laminocostotransversoplasty for ventral meningiomas in the thoracic region.
J Orthop Sci
PUBLISHED: 06-10-2009
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Treatment of ventral lesions to the spinal cord in the thoracic spinal canal (e.g., meningiomas) are surgical challenges. Original or modified costotransversectomy has been commonly used for extirpation of such lesions. However, these techniques incur great loss of posterior elements followed by spinal instability that requires spinal fusion. The authors have developed a new surgical technique that combined the advantages of posterolateral exposures and recapping laminoplasty (recapping T-saw laminocostotransversoplasty). The purpose of this study was to examine the safety and effectiveness of this technique for surgical excision of ventrally located meningiomas in the thoracic region.
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Prevention of pin tract infection with titanium-copper alloys.
J. Biomed. Mater. Res. Part B Appl. Biomater.
PUBLISHED: 06-10-2009
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The most frequent complication in external fixation is pin tract infection. To reduce the incidence of implant-associated infection, many published reports have looked at preventing bacterial adhesion by treating the pin surface. This study aimed to evaluate the antibacterial activity of a Titanium-Copper (Ti-Cu) alloy on implant infection, and to determine the potential use of the Ti-Cu alloy as a biomaterial. Two forms of Ti-Cu alloys were synthesized: one with 1% Cu and the other with 5% Cu. For analyzing infectious behavior, the implants were exposed to Staphylococcus aureus and Escherichia coli. The reaction of pathogens to the Ti-Cu alloys was compared with their reaction to stainless steel and pure titanium as controls. Both Ti-Cu alloys evidently inhibited colonization by both bacteria. Conversely, cytocompatibility studies were performed using fibroblasts and colony formation on the metals was assessed by counting the number of colonies. Ti-1% Cu alloy showed no difference in the number of colonies compared with the control. External fixator pins made of Ti-Cu alloys were evaluated in a rabbit model. The tissue-implant interactions were analyzed for the presence of infection, inflammatory changes and osteoid-formation. Ti-1% Cu alloy significantly inhibited inflammation and infection, and had excellent osteoid-formation. Copper blood levels were measured before surgery and at 14 days postoperatively. Preoperative and postoperative blood copper values were not statistically different. Overall, it was concluded that Ti-Cu alloys have antimicrobial activity and substantially reduce the incidence of pin tract infection. Ti-1% Cu alloy shows particular promise as a biomaterial.
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Flexion contracture of the fingers caused by sarcoidosis: an 11-year follow-up.
Scand J Plast Reconstr Surg Hand Surg
PUBLISHED: 04-30-2009
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We report the long-term result of operative treatment of a flexion contracture of the fingers resulting from sarcoidosis, in which the contracture recurred. Even with complete excision of the granulomatous lesion, a new lesion may appear in a previously healthy area, so a radical cure by operation alone is difficult.
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Histological examination of frozen autograft treated by liquid nitrogen removed after implantation.
J Orthop Sci
PUBLISHED: 04-22-2009
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Several oncological sterilization methods involving autoclaving, irradiation, or pasteurization have been developed for limb reconstruction of large bone defects following tumor excision. Studies involving histological examinations of these autografts have all found that osteogenesis occurs slowly. We have used frozen autografts treated by liquid nitrogen for limb reconstruction and have achieved excellent results for bone union. To determine if frozen autografts exhibit early bone remodeling, we investigated the repair processes of the frozen bones.
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Caffeine-potentiated chemotherapy for metastatic osteosarcoma.
J Orthop Sci
PUBLISHED: 04-15-2009
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The prognosis for patients with metastatic osteosarcoma is still poor despite the development of effective adjuvant and neoadjuvant chemotherapy regimens. We have developed caffeine-potentiated chemotherapy for treatment of high-grade bone and soft tissue sarcomas based on the ability of caffeine to enhance the cytocidal effects of anticancer drugs. We report results of caffeine-potentiated chemotherapy for patients with osteosarcoma with pulmonary metastases.
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Local application of olprinone for promotion of peripheral nerve regeneration.
J Orthop Sci
PUBLISHED: 03-27-2009
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Olprinone was applied locally to the sciatic nerves of rats, and nerve regeneration activity was examined in relation to heat shock protein (HSP)27 expression.
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A mechanical analysis of femoral resurfacing implantation for osteonecrosis of the femoral head.
J Arthroplasty
PUBLISHED: 03-26-2009
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Hip resurfacing is becoming a popular procedure for treating osteonecrosis of the femoral head. However, the biomechanical changes that occur after femoral resurfacing have not been fully investigated with respect to the individual extent of the necrosis. In this study, we evaluated biomechanical changes at various extents of necrosis and implant alignments using the finite element analysis method. We established 3 patterns of necrosis by depth from the surface of femoral head and 5 stem angles. For these models, we evaluated biomechanical changes associated with the extent of necrosis and the stem alignment. Our results indicate that stress distribution near the bone-cement interface increased with expansion of the necrosis. The maximum stress on the prosthesis was decreased with stem angles ranging from 130° to 140°. The peak stress of cement increased as the stem angle became varus. This study indicates that resurfacing arthroplasty will have adverse biomechanical effects when there is a large extent of osteonecrosis and excessive varus or valgus implantation of the prosthesis.
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Systemic targeting of primary bone tumor and lung metastasis of high-grade osteosarcoma in nude mice with a tumor-selective strain of Salmonella typhimurium.
Cell Cycle
PUBLISHED: 03-20-2009
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We report here a new targeting strategy for primary bone tumor and lung metastasis with a modified auxotrophic strain of Salmonella typhimurium. We have previously developed the genetically-modified strain of S. typhimurium, selected for tumor targeting and therapy in vivo. Normal tissue is cleared of these bacteria even in immunodeficient athymic mice with no apparent side effects. In this study, the tumor-targeting strain of S. typhimurium, termed A1-R, was administered i.v. to nude mice which have primary bone tumor and lung metastasis. Primary bone tumor was obtained by orthotopic intra-tibial injection of 5 x 10(5) 143B-RFP (red fluorescent protein) human osteosarcoma cells. One group of mice was treated with A1-R expressing GFP (green fluorescent protein) and another group was used a as control. A1-R (5 x 10(7) colony-forming units) was injected in the tail vein three times on a weekly basis. On day 28, lung samples were excised and observed with the Olympus OV100 Small Animal Imaging System. The size of the primary tumor and RFP intensity of lung metastasis were measured. Primary bone tumor size (fluorescence area [mm(2)]) was 232 +/- 70 in the untreated group and 95 +/- 23 in the treated group (p < 0.05). RFP intensity of the lung metastasis was 3 +/- 1.5 x 10(6) in the untreated group and 0.42 +/- 0.33 x 10(6) in the treated group (p < 0.05). Therefore, bacterial treatment was effective for both primary bone tumor and lung metastasis.
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Surgical site infection in spinal metastasis: risk factors and countermeasures.
Spine
PUBLISHED: 03-14-2009
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A retrospective review (phase 1) and prospective clinical study (phase 2).
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Occlusive dressing for large soft tissue defects following soft tissue tumor excision.
J Orthop Sci
PUBLISHED: 03-13-2009
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Reconstructive surgery using pedicles or free muscle-skin flaps and skin grafting reduces wound complications and promotes favorable limb function; however, the sacrifice of normal tissue remains problematic and complicated. Occlusive dressings are widely employed for management of injuries, burns, and surgical wounds. However, their effectiveness for treating soft tissue defects following a soft tissue tumor excision has not been fully elucidated. The purpose of this study was to evaluate the effectiveness and safety of an occlusive dressing treatment method for soft tissue defects following soft tissue tumor excisions.
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Mechanical evaluation by patient-specific finite element analyses demonstrates therapeutic effects for osteoporotic vertebrae.
J Mech Behav Biomed Mater
PUBLISHED: 03-11-2009
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Osteoporosis can lead to bone compressive fractures in the lower lumbar vertebrae. In order to assess the recovery of vertebral strength during drug treatment for osteoporosis, it is necessary not only to measure the bone mass but also to perform patient-specific mechanical analyses, since the strength of osteoporotic vertebrae is strongly dependent on patient-specific factors, such as bone shape and bone density distribution in cancellous bone, which are related to stress distribution in the vertebrae. In the present study, patient-specific general (not voxel) finite element analyses of osteoporotic vertebrae during drug treatment were performed over time. We compared changes in bone density and compressive principal strain distribution in a relative manner using models for the first lumbar vertebra based on computer tomography images of four patients at three time points (before therapy, and after 6 and 12 months of therapy). The patient-specific mechanical analyses indicated that increases in bone density and decreases in compressive principal strain were significant in some osteoporotic vertebrae. The data suggested that the vertebrae were strengthened structurally and the drug treatment was effective in preventing compression fractures. The effectiveness of patient-specific mechanical analyses for providing useful and important information for the prognosis of osteoporosis is demonstrated.
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Total en bloc spondylectomy for spinal tumors: surgical techniques and related basic background.
Orthop. Clin. North Am.
PUBLISHED: 02-25-2009
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The authors group has developed a new surgical technique of spondylectomy (vertebrectomy) called "total en bloc spondylectomy" (TES). This technique is different from spondylectomy in that it involves en bloc removal of the lesion, that is, removal of the whole vertebra, body and lamina, as one compartment. The surgical technique of TES has been remarkably improved based on adequate knowledge and consideration of the surgical anatomy, physiology, and biomechanics of the spine and spinal cord. Review of the developmental process of this operation leads to recognition of the tips, pitfalls, and solutions.
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Impact of serum caffeine monitoring on adverse effects and chemotherapeutic responses to caffeine-potentiated chemotherapy for osteosarcoma.
J Orthop Sci
PUBLISHED: 02-18-2009
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Caffeine can safely enhance the cytocidal effects of anticancer drugs through its DNA repair-inhibiting effect. We have demonstrated in several studies that caffeine-potentiated chemotherapy induces a high complete response rate in patients with osteosarcoma. The present study focused on monitoring and adjusting serum caffeine levels during caffeine-potentiated chemotherapy to reduce adverse effects.
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Cancer metastasis directly eradicated by targeted therapy with a modified Salmonella typhimurium.
J. Cell. Biochem.
PUBLISHED: 02-10-2009
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Cancer metastasis is the life-threatening aspect of cancer and is usually resistant to standard treatment. We report here a targeted therapy strategy for cancer metastasis using a genetically-modified strain of Salmonella typhimurium. The genetically-modified strain of S. typhimurium is auxotrophic for the amino acids arginine and leucine. These mutations preclude growth in normal tissue but do not reduce bacterial virulence in cancer cells. The tumor-targeting strain of S. typhimurium, termed A1-R, and expressing green fluorescent protein (GFP), was administered to both axillary lymph and popliteal lymph node metastasis of human pancreatic cancer and fibrosarcoma, respectively, as well as lung metastasis of the fibrosarcoma in nude mice. The bacteria were delivered via a lymphatic channel to target the lymph node metastases and systemically via the tail vein to target the lung metastasis. The cancer cells expressed red fluorescent protein (RFP) in the cytoplasm and GFP in the nucleus linked to histone H2B, enabling color-coded real-time imaging of the bacteria targeting the metastatic tumors. After 7-21 days of treatment, the metastases were eradicated without the need of chemotherapy or any other treatment. No adverse effects were observed. This new strategy demonstrates the clinical potential of targeting and curing cancer metastasis with engineered bacteria without the need of toxic chemotherapy.
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Transvertebral herniotomy for T2/3 disc herniation--a case report.
J Spinal Disord Tech
PUBLISHED: 02-05-2009
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A case report of a 51-year-old man with acute myelopathy owing to T2/3 disc herniation that was treated with transvertebral herniotomy.
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Eosinophilic granuloma of the lumbar spine in an adult.
Orthopedics
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Eosinophilic granuloma of the spine is a common benign disease in children and adolescents that rarely affects adults.This article describes the case of a 32-year-old woman with a solitary eosinophilic granuloma presenting as a local lytic lesion at the L4 vertebral body. She presented with a 2-month history of low back pain without neurological deficits. Plain radiographs showed a lytic lesion of the L4 vertebral body. Computed tomography scans showed an osteolytic lesion surrounded by partial sclerotic change of the L4 vertebral body. Magnetic resonance imaging revealed a low-intensity lesion on T1-weighted images and a high-intensity lesion on T2-weighted images. A computed tomography-guided transpedicular needle biopsy of the L4 vertebral body was performed. The histological specimen stained with hematoxylin-eosin revealed features of eosinophilic granuloma with aggregates of Langerhans cells. On immunological studies, the diagnosis of eosinophilic granuloma was facilitated by diffuse immunoreactivity of S-100 protein and CD1a. For the 3-month period after biopsy, the patient was fitted with a corset and allowed to walk. Four months after biopsy, computed tomography scans showed that remodeling of the destructive lesion of the L4 vertebral body was occurring. Two years after initial onset, the patient had complete relief of low back pain and no neurologic deficit. Computed tomography scans showed full reconstitution of the lesion. This was a rare case of successful conservative treatment of eosinophilic granuloma of the lumbar spine in an adult. Conservative treatment may be considered in a patient with an eosinophilic granuloma with no neurological deficit or spinal instability.
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A glass foreign body migrating into the lumbar spinal canal: a case report.
J Orthop Surg (Hong Kong)
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We report on a 12-year-old boy in whom a glass fragment migrated into the lumbar spinal canal causing low back pain and radiculopathy 6 years after injury. Computed tomography showed a foreign body in the anterior spinal canal of L5/S1. The patient underwent recapping T-saw laminoplasty to remove the foreign body. Scar formation was noted at the anterior dura. The glass fragment seemed to have penetrated into the intradural space from an anterior site. Postoperatively, the pain resolved immediately. At the 9-year follow-up, the alignment of the lumbar spine and healing of L5 was good, with no features of aseptic necrosis.
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Giant cell tumor expanded into the thoracic cavity with spinal involvement.
Orthopedics
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This article describes a case of a giant cell tumor that expanded into the thoracic cavity and through the spinal canal into the vertebrae. A 36-year-old man presented with a 6-month history of back pain and dyspnea. Plain chest radiographs showed a huge mass accompanied by right pleural effusion. The mass involved the 12th thoracic spine, and the spinal cord was severely compressed. The tumor was resected with a 2-stage procedure. As a first stage to separate the tumor from the anterior vital structures under direct vision, thoracic surgeons performed a right thoracotomy with chest wall reconstruction from the 8th to 11th ribs. The right lung and inferior vena cava were gently retracted, and the tumor was carefully detached from these structures. We were not able to separate the tumor from the right diaphragm due to severe invasion; therefore, we performed partial resection of the right diaphragm with the tumor. After excision of the anterior part of the tumor, the thoracic wall was reconstructed with the right eighth rib and Marlex mesh. When the patients general condition improved 2 weeks later, spondylectomy by posterior approach was performed. We achieved excision of a giant cell tumor that had expanded into the thoracic cavity and through the spinal canal into the vertebrae. The patient had achieved full rehabilitation with no neurological or respiratory abnormalities at 7 years postoperatively.
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