Biomedical subjects

S Ebara

Publications and source records attributed to S Ebara.

At least 19 recordsLinked to original sources

PubMed2004

Biosynthesis of 32P-labelled hydroxocobalamin and a study of its behaviour in rats.

Using Propionibacterium freudenreichii and 32P-ATP, batches of 32P-labelled cobalamin (Cbl) were biosynthesized with a maximum specific activity of 61 microCi/mg, i.e. about 100 times higher than previously reported. Pharmacological doses mixed with 57Co-Cbl were injected subcutaneously in the form of hydroxo-Cbl into rats subsequently killed 5-20 days later. The two labelled Cbls were distributed in approximately the same way, the highest concentration being found in kidney (typical for rats) and about one-fifth of that in liver. These findings tallied with previous observations with radioactive cyano-Cbl and microbiological assay. In all injected rats, the 57Co/32P ratio was lower in liver than in kidney. Drugs eradicating the intestinal flora had no influence. In rats receiving the vitamin orally, the ratio was higher in liver than in kidney. All of our findings could be due to formation of a cobinamide-like compound lacking phosphorus. It is concluded that we have produced radiophosphorus-labelled Cbl that enables studies in vivo.

Administration, Oral↗

PubMed2003

A neurofibromatosis type 1 patient with severe kyphoscoliosis and intrathoracic meningocele.

The patient presented with neurofibromatosis and a dystrophic kyphoscoliosis around the cervico-thoracic junction. When the patient was 59 years old, he started to suffer from dyspnea caused by an intrathoracic meningocele in the upper left thoracic cavity. A wide laminectomy from T2 to T5 was performed and the meningocele was resected. Although the dyspnoea disappeared postoperatively, the patient started to neurologically deteriorate. Laminectomy alone caused instability around the apex of the kyphosoliosis and spinal cord compression. Halo cast was applied and brought remarkable recovery of neurologic deficits. This result encouraged us to perform posterior fusion in situ from C3 to L2 with bone graft from the iliac crests and the Luque technique in conjunction with the Isola system. This resulted in the patient being able to walk again. The removal of the posterior element predisposes the patient to unstable postlaminectomy kyphosis and removes valuable bone stock required for posterior spinal fusion. For this reason, spinal fusion should have been conducted during surgery for the patient's meningocele.

Bone Transplantation↗

PubMed2003

A case of mucopolysaccharidosis IV with lower leg paresis due to thoraco-lumbar kyphoscoliosis.

We treated a patient of type IV mucopolysaccharidosis (Morquio's disease) with lower leg paresis due to kyphoscoliosis. A 65-year-old woman presented with Morquio's disease. A lateral radiograph demonstrated the classic bullet-shaped vertebrae and a 65 degrees thoraco-lumbar kyphosis. After the age of 60, she suffered from numbness in both lower legs and walking disturbance. Bilateral patellae-tendon reflexes were exaggerated. MRI showed compression of the spinal cord around T12 to L2 with a highlighted area of change inside the spinal cord. Myelography and computed tomography after the myelography showed narrowing of the sub-arachnoidal space and deformation of the spinal cord around the T12 to L2 levels. Severe vertebral osteoporosis made it necessary to first perform posterior correction of the kyphosis and fusion. The curve was stabilised with the Luque method from T7 to L4. Her neurological condition markedly recovered, but 1 year after surgery her neurological condition again began to deteriorate, resulting in walking disturbance. For this reason, anterior decompression and fusion through a lateral thoracotomy was undertaken. Decompression of the spinal cord and a bone graft from the iliac crest were attained. The patient's neurological condition again improved, but not as much as immediately after the first operation.

Aged↗

PubMed2002

Gene therapy for prostate cancer: toxicological profile of four HSV-tk transducing adenoviral vectors regulated by different promoters.

Adenoviral vector delivery of the Herpes simplex virus thymidine kinase (HSV-tk) gene in combination with the prodrug ganciclovir (GCV) has been tested in phase I clinical trials for prostate cancer and found to exhibit a satisfactory toxicity profile. We have developed additional adenoviral vectors with differing promoters to optimize the expression profile and in the present study evaluate the potential systemic toxicity of these vectors. Four recombinant adenoviral vectors that express the HSV-tk gene were generated using three different promoters: CMV (leftward orientation); RSV (both rightward and leftward orientation); and the mouse caveolin-1 (cav-1) promoter (leftward orientation). Efficacy was determined in vitro by cytotoxicity assays in a mouse prostate cancer cell line, RM-9, and in vivo by treating orthotopic tumors. Potential toxicity was evaluated from liver histology and apoptotic cell counts and enzyme levels in the serum following intravenous adenoviral vector injection. Although there were differences in HSV-tk expression at the protein level among the four vectors there were no significant differences in in-vitro cytotoxicity studies with GCV or in vivo in tumor growth suppression of an orthotopic mouse prostate cancer model in GCV treated mice. Intravenous delivery of high doses of all adenoviral vectors lead to abnormalities in liver function as measured by specific serum markers and histological evaluation of liver tissue and increased levels of apoptosis in the liver. These abnormalities were most prevalent with the vector containing the CMV promoter and the rightward oriented RSV promoter. They were least prevalent in the vector regulated by the cav-1 promoter. Upregulation of specific chemokines, MIP-2 and MIP-1beta was correlated with apoptotic counts. Our results demonstrate that comprehensive toxicological analysis of adenoviral vectors provides internally consistent information that can differentiate vectors with comparable efficacy based on toxicity. In these studies vectors with the cav-1 promoter-driven and leftward RSV-driven HSV-tk gene demonstrated minimal toxicities with cytotoxic effectiveness comparable to more toxic vectors. Our studies further suggest that promoter selection can influence the toxic effects of an adenoviral gene therapy vector.

Adenocarcinoma↗

PubMed2001

Cobalamin deficiency results in severe metabolic disorder of serine and threonine in rats.

Dietary cobalamin (vitamin B12; Cbl) deficiency caused significant increases in plasma serine, threonine, glycine, alanine, tyrosine, lysine and histidine levels in rats. In particular, the serine and threonine levels were over five and eight times, respectively, higher in the Cbl-deficient rats than those in the sufficient controls. In addition, some amino acids, including serine and threonine, were excreted into urine at significantly higher levels in the deficient rats. When Cbl was supplemented into the deficient rats for 2 weeks, in coincidence with the disappearance of the urinary excretion of methylmalonic acid (an index of Cbl deficiency), the plasma serine and threonine levels were normalized. These results indicate that Cbl deficiency results in metabolic disorder of certain amino acids, including serine and threonine. The expression level of hepatic serine dehydratase (SDH), which catalyzes the conversion of serine and threonine to pyruvate and 2-oxobutyrate, respectively, was significantly lowered by Cbl deficiency, even though Cbl does not participate directly in the enzyme reaction. The SDH activity in the deficient rats was less than 20% of that in the sufficient controls, and was normalized 2 weeks after the Cbl supplementation. It is thus suggested that the decrease of the SDH expression relates closely with the abnormalities in the plasma and urinary levels of serine and threonine in the Cbl-deficient rats.

Animals↗

PubMed2001

Early-phase enhanced inflammatory reaction after spinal instrumentation surgery.

STUDY DESIGN: The erythrocyte sedimentation rate, C-reactive protein, white blood cell count, and body temperature were measured prospectively in patients after two types of spinal surgery without complications and three cases of infection after spinal instrumentation surgery. OBJECTIVES: To investigate the effects of instrumentation on postoperative inflammatory reaction, and to describe early detection of postoperative wound infection. SUMMARY OF BACKGROUND DATA: In thoracic and abdominal surgery as well as hip arthroplasty, C-reactive protein has proved more valuable than erythrocyte sedimentation rate for early detection of postoperative infectious complications. It has not yet been established, however, how inflammatory parameters change after surgery when spinal instruments have been inserted into the body. METHODS: For this study, two groups of patients were examined: a control group that underwent spinal decompression surgery without instrumentation (n = 36) and another group that underwent spinal decompression and fusion surgery with spinal instrumentation (n = 37). The erythrocyte sedimentation rate, C-reactive protein, white blood cell count, and body temperature were recorded 1 day before surgery and on days 0 to 4, 7, 11, 14, 21, 28, and 42 after surgery. RESULTS: Inflammatory indexes (i.e., C-reactive protein, erythrocyte sedimentation rate, white blood cell count, and body temperature) were significantly higher for the surgery with instrumentation than for the spinal decompression surgery without instrumentation. Multiple regression analysis showed that C-reactive protein and erythrocyte sedimentation rate peaks significantly correlated with the use of instrumentation (C-reactive protein: P = 0.000257, erythrocyte sedimentation rate: P = 0.000132). In the patients with infection after spinal instrumentation surgery, C-reactive protein, white blood cell count, and body temperature started to increase again 4 to 11 days after surgery. The elevation of erythrocyte sedimentation rate levels was prolonged. CONCLUSIONS: Erythrocyte sedimentation rate and C-reactive protein display a significantly higher reaction after spinal surgery with instrumentation. Renewed elevation of C-reactive protein, white blood cell count, and body temperature after postoperative days 4 to 7 may be a critical sign of postoperative infection.

Adult↗

PubMed2001

Caveolin-1 mediates testosterone-stimulated survival/clonal growth and promotes metastatic activities in prostate cancer cells.

Previously, we demonstrated that up-regulation of caveolin-1 (cav-1) was associated with prostate cancer metastasis, biochemical recurrence after radical prostatectomy, and androgen insensitivity. The objective of this study was to characterize the regulation of cav-1 by testosterone (T) and to test the effects of cav-1 on prostate cancer cell survival/clonal growth and metastatic activities. Our results demonstrated that T up-regulated cav-1 protein levels in part through transcriptional regulation and significantly enhanced survival of prostate cancer cell lines ABAC3 and LNCaP after serum starvation (>40% and >60% increased viability, respectively) and in an extended clonogenic assay (approximately 4-fold and 6-fold increase in colonies, respectively). Importantly, antisense cav-1 inhibited the survival effects of T in these assay systems. Modest but not high levels of adenoviral vector-mediated cav-1 expression alone also significantly increased viability (>40%) and clonal growth (10-fold increase in colonies) after serum starvation. Analysis of spontaneous metastasis in stably transfected antisense cav-1 mouse prostate cancer cell clones demonstrated reduction of spontaneous lymph node metastasis incidence (13%), spontaneous lymph node metastasis volume (46%), and experimental lung metastasis incidence (40%) compared with vector control cell clones. Surgical castration further reduced spontaneous lymph node metastasis incidence and volume (18% and 28%, respectively) in antisense cancer cell clones, but not in vector control clones. Our studies demonstrate that cav-1 is a downstream effector of T-mediated prostate cancer cell survival/clonal growth and that modest levels of cav-1 can independently promote prostate cancer cell survival/clonal growth and metastatic activities.

Animals↗

PubMed2001

Secreted caveolin-1 stimulates cell survival/clonal growth and contributes to metastasis in androgen-insensitive prostate cancer.

Caveolin-1 is an integral protein of caveolae, known to play important roles in signal transduction and lipid transport. We demonstrate that caveolin-1 expression is significantly increased in primary and metastatic human prostate cancer after androgen ablation therapy. We also show that caveolin-1 is secreted by androgen-insensitive prostate cancer cells, and that this secretion is regulated by steroid hormones. Significantly, caveolin-1 was detected in the MDL(3) fraction of serum specimens from patients with advanced prostate cancer and to a lesser extent in normal subjects. Conditioned media from high passage caveolin-1 secreting, androgen-insensitive, LNCaP cells stimulated increased viability and clonal growth of low passage, caveolin-1-negative, androgen-sensitive, LNCaP cells in vitro, and this effect was blocked by treating the media with caveolin-1 antibody. i.p. injections of caveolin-1 antibody suppressed the orthotopic growth and spontaneous metastasis of highly metastatic, androgen-insensitive caveolin-1-secreting mouse prostate cancer. Overall, our results establish caveolin-1 as an autocrine/paracrine factor that is associated with androgen-insensitive prostate cancer. We demonstrate the potential for caveolin-1 as a therapeutic target for this important malignancy.

Androgen Antagonists↗

PubMed2001

Progressive scoliosis in cri-du-chat syndrome over a 20-year follow-up period: a case report.

STUDY DESIGN: A long-term follow-up study of a patient who had scoliosis associated with cri-du-chat syndrome was performed. OBJECTIVE: To describe for the first time the characteristics and natural course of progressive scoliosis in a patient with cri-du-chat syndrome. SUMMARY OF BACKGROUND DATA: Scoliosis is a common condition in patients with cri-du-chat syndrome. However, there are no reports on the clinical characteristics and course of this spinal deformity. METHODS: The current condition and radiographs of a 33-year-old man with cri-du-chat syndrome were assessed. The records and serial radiographs of his spine were reviewed retrospectively over a 29-year period, between ages 4 and 33 years. RESULTS: The scoliosis had started before the initial radiographic examination and progressed rapidly during the growth period. After this stage, slow but continuous progression was observed over the next 10 years. The final curvature was quite substantial, measuring 119 degrees. CONCLUSIONS: To determine the most appropriate treatment for the scoliosis associated with cri-du-chat syndrome, the characteristics and natural course of the scoliosis should be clarified. Although this first report on this type of scoliosis is informative, more cases and further studies are needed.

Cri-du-Chat Syndrome↗

PubMed2001

Characterization of a vitamin B12 compound from unicellular coccolithophorid alga (Pleurochrysis carterae).

A unicellular coccolithophorid alga, Pleurochrysis carterae, contained 125.4 +/- 1.2 microg of vitamin B12 per 100 g dry cell weight of the lyophilized algal cells. A vitamin B12 compound was purified from the lyophilized algal cells and partially characterized. The silica gel 60 TLC and reversed-phase HPLC patterns of the purified pink-colored compound were identical to those of authentic vitamin B12, but not those of vitamin B12 analogues inactive for humans. When 22-week-old B12-deficient rats which excreted substantial amounts of methylmalonic acid (75.5 +/- 12.3 mg/day) in urine were fed the P. carterae (10 g per kg diet)-supplemented diet for 12 d, urinary methylmalonic acid excretion (as an index of vitamin B12 deficiency) of the rats became undetectable and hepatic vitamin B12 level of the rats was significantly increased.

Animals↗

PubMed2001

Combination gene therapy with adenoviral vector-mediated HSV-tk+GCV and IL-12 in an orthotopic mouse model for prostate cancer.

We previously demonstrated significant therapeutic activities associated with adenoviral vector-mediated Herpes Simplex Virus/thymidine kinase (AdHSV-tk) with ganciclovir (GCV) in situ gene therapy in the RM-1 orthotopic mouse prostate cancer model and interleukin-12 (AdmIL-12) in situ gene therapy in the RM-9 orthotopic mouse prostate model for prostate cancer. In both protocols, local cytotoxicity and activities against pre-established lung metastases were demonstrated. To test whether combined AdHSV-tk+GCV+IL-12 gene therapy would lead to enhanced therapeutic effects when compared to either treatment alone, we used RM-9 mouse prostate cancer cells in both orthotopic and pre-established lung metastases models of prostate cancer. Combined treatment with a single injection of optimal doses of AdHSV-tk+GCV or AdmIL-12 led to significantly increased suppression of orthotopic tumor growth. IL-12 gene therapy alone was more effective than AdHSV-tk+GCV in suppressing spontaneous lymph node metastases and pre-established lung metastases but combination gene therapy did not result in additional anti-metastatic activities. Combination gene therapy also did not achieve significantly better animal survival compared to AdHSV-tk+GCV or AdmIL-12 alone. Analysis of localized antitumor activities demonstrated that AdHSV-tk+GCV therapy induced higher levels of necrosis compared to AdmIL-12 or combination therapy. However, both treatments alone and combination therapy produced similar increases in apoptotic index. To address the possible mechanisms of locally co-operative cytotoxic activities, we analyzed the systemic natural killer (NK) response and the numbers of tumor-infiltrating immune cells using quantitative immunohistochemical analysis. AdHSV-tk+GCV therapy alone led to detectable increases in iNOS-positive cells, CD4+and CD8+T-cells and moderately increased numbers of F4/80 (macrophage selective)-positive cells within treated tumors. In contrast, AdmIL-12 elicited a highly robust pattern of tumor infiltration for all four of these immune cells that was in general mimicked by combination therapy. Further analysis of the accumulation of transforming growth factor-beta1 (TGF-beta1) immunohistochemical staining demonstrated that AdHSV-tk+GCV treatment, but not AdmIL-12 treatment, produced cancer cell-associated increases in this cytokine relative to control Ad-beta-gal injections. Interestingly, local injection with AdHSV-tk+GCV induced significant splenocyte-derived NK cell cytolytic activities with maximal response 7 days following treatment, whereas AdmIL-12 injection produced significantly higher NK activity with maximal response 2 days following injection. The combined treatment produced a higher systemic NK response over the 14-day treatment period. Depletion of NK cells in vivo demonstrated that this immunocyte subpopulation was responsible for early locally cytotoxic activities induced by AdHSV-tk+GCV but not AdmIL-12 and that NK activities were largely responsible for activities against pre-established metastases generated by both gene therapy protocols. Prostate Cancer and Prostatic Diseases (2001) 4, 44-55

Journal Article↗

PubMed2001

Feeding dried purple laver (nori) to vitamin B12-deficient rats significantly improves vitamin B12 status.

To clarify the bioavailability of vitamin B12 in lyophylized purple laver (nori; Porphyra yezoensis), total vitamin B12 and vitamin B12 analogue contents in the laver were determined, and the effects of feeding the laver to vitamin B12-deficient rats were investigated. The amount of total vitamin B12 in the dried purple laver was estimated to be 54.5 and 58.6 (se 5.3 and 7.5 respectively) microg/100 g dry weight by Lactobacillus bioassay and chemiluminescent assay with hog intrinsic factor respectively. The purple laver contained five types of biologically active vitamin B12 compounds (cyano-, hydroxo-, sulfito-, adenosyl- and methylcobalamin), in which the vitamin B12 coezymes (adenosyl- and methylcobalamin) comprised about 60 % of the total vitamin B12. When 9-week-old vitamin B12-deficient rats, which excreted substantial amounts of methylmalonic acid (71.7(se 20.2) micromol/d) in urine, were fed the diet supplemented with dried purple laver (10 microg/kg diet) for 20 d, urinary methylmalonic acid excretion (as an index of vitamin B12 deficiency) became undetectable and hepatic vitamin B12 (especially adenosylcobalamin) levels were significantly increased. These results indicate that vitamin B12 in dried purple laver is bioavailable to rats.

Animals↗

PubMed2001

Evaluation of thoracic myelopathy by transcranial magnetic stimulation.

It is sometimes difficult to determine the appropriate surgical site in patients with thoracic myelopathy with diffuse or multisegmental lesions. To solve this problem, a magnetic stimulation study was carried out. Seven patients with myelopathy and 10 healthy control subjects were examined. Transcranial magnetic stimulation was applied and the motor evoked potentials (MEPs) of the intercostal muscles were recorded. The MEP latencies for the two groups were then compared. In patients with thoracic myelopathy, the MEP latencies caudal to the lesion were more extended than those of the control subjects. This method could identify the levels at which myelopathy originates in patients with a radiologically visible lesion. This method has the potential to be used for deciding the surgical site at the level responsible for myelopathy in cases with multiple or diffused compression.

Adult↗

PubMed2001

In situ gene therapy for prostate cancer: immunomodulatory approaches.

The development of effective treatments for prostate cancer is thwarted by the natural history of the disease. The biological and clinical potential of most individual cancers is uncertain. In many cases the disease will not progress to clinical significance but experimental and clinical studies indicate that prostate cancer can and may metastasis early in the course of the disease from relatively small foci (i.e., not necessarily the largest or index cancer). Localised prostate cancer is potentially curable with localised therapies (radical prostatectomy or irradiation therapy). However, there are no curative therapies for metastatic prostate cancer. Gene therapy, especially those approaches with an immunomodulatory component, may provide additional therapeutic options with the potential to affect both localised and systemic disease. We have pioneered the development and application of in situ gene therapy protocols using adenoviral vectors to transduce specific genes that generate cytotoxic activity and/or a systemic antitumour immune response. In addition we have completed initial studies that demonstrate the therapeutic potential of adenoviral vector-mediated gene modified cell-based vaccines. Our review discusses preclinical studies focused on the development of immunostimulatory in situ gene therapy approaches that hopefully will provide novel and effective treatments for localised and metastatic prostate cancer.

Animals↗

PubMed2001

In situ prostate cancer gene therapy using a novel adenoviral vector regulated by the caveolin-1 promoter.

Caveolin-1, a structural component of caveolae, is overexpressed in metastatic and androgen-resistant prostate cancer and highly expressed in tumor-associated endothelial cells. The mouse cav-1 promoter was cloned and placed upstream of the HSV-tk gene in an adenoviral vector (Adcav-1tk) and compared with a cytomegalovirus (CMV) or Rous sarcoma virus (RSV) promoter-driven HSV-tk, AdCMVtk and AdRSVtk vectors, respectively. Mouse and human prostate cancer cells and mouse endothelial cells were infected with Adcav-1tk, AdCMVtk or control vectors without the HSV-tk gene (Adcav-1 and AdCMV) and subsequently treated with ganciclovir (GCV). GCV-mediated in vitro cytotoxicity induced by the Adcav-1tk vector was comparable to that for AdCMVtk in multiple mouse and human prostate cancer cell lines. To evaluate the activity of Adcav-1tk in vivo, orthotopic mouse prostate cancer tumors were generated with RM-9 cells and injected in situ with Adcav-1tk, AdCMVtk, AdRSVtk, or AdCMVbetagal (control) and treated with GCV. All three HSV-tk transducing vectors produced statistically significant reductions in wet weight and increased apoptotic indices compared with the control vector. However, only Adcav-1tk produced significant necrosis, and only Adcav-1tk and AdRSVtk caused significant decreases in microvessel density. In conclusion, Adcav-1tk demonstrated efficacy in vitro and in vivo in preclinical models of prostate cancer. Our results suggest that the cav-1 promoter may have unique benefits in targeting gene therapy to prostate cancer and its associated vasculature.

Adenoviridae↗

PubMed2000

Reduced infiltration of tumor-associated macrophages in human prostate cancer: association with cancer progression.

Tumor-associated macrophages (TAMs) are highly active immune effector cells that may either positively or negatively regulate the growth of various malignant cells, depending on the biological context. However, the role of TAMs in human prostate cancer progression is unclear. TAMs were immunohistochemically labeled using a monoclonal (CD68) antibody in radical prostatectomy specimens derived from 81 prostate cancer patients. CD68-positive cells were counted with the aid of a microscope and expressed as macrophage index (MphiI), including TAMs/mm2 total tumor tissue (MphiItotal), TAMs/mm2 tumor stroma (MphiIstroma), and TAMs/mm2 cancer cell area (MphiIcancer). MphiIs were analyzed in association with patients' clinical and pathological stage, recurrence status, and histological grade of the cancer. There were significant inverse relationships between MphiItotal and MphiIstroma and clinical stage (P = 0.016 and P = 0.006, respectively). Reduced MphiItotal was also associated with the presence of positive lymph nodes (P = 0.010). Interestingly, although all of the MphiIs differed between Gleason score groups, only MphiIcancer was positively associated with Gleason score. Univariate analysis of MphiItotal and multivariate analysis of MphiItotal with specific pathological markers revealed that MphiItotal was an independent predictor for disease-free survival after surgery (Cox proportional hazard model, P = 0.044 and P = 0.007, respectively). For patients with high MphiItotal (> or = 185.8, the mean MphiItotal value), the disease-free probability 5 years after surgery was 0.75, which was significantly higher than for those with low MphiItotal (0.31, P = 0.0008). Additional immunohistochemical studies that evaluated cytotoxicity-related biomarkers in stroma-associated mononuclear cells suggested reduced functional activities in highly aggressive prostate cancer compared with less aggressive disease. Our results indicate that reduced MphiItotal is a novel prognostic marker for prostate cancer.

Aged↗

PubMed2000

A new system for the anterior restoration and fixation of thoracic spinal deformities using an endoscopic approach.

STUDY DESIGN: A report on the results of animal experiments in which the authors' new system that enables the anterior correction and fixation of thoracic spinal deformity by use of a thoracic endoscope and small incisions was used. The results suggest that the new approach involving thoracoscopic anterior correction and fusion for thoracic spinal deformity could be adapted successfully for the clinic. OBJECTIVE: To develop a new system that enables the anterior correction and fixation of thoracic spinal deformity by use of a thoracic endoscope and small incisions. SUMMARY OF BACKGROUND DATA: Anterior correction and fusion through open thoracotomy have been applied mainly for thoracic scoliosis because this approach provides effective correction with short fusion. However, excellent visualization of the spine during thoracic surgical procedures led to the development of thoracoscopic spine surgery. Therefore, the authors postulated that a thoracoscopic approach could allow not only discectomy but also correction and fusion of the deformed thoracic spine in a single surgical event. METHODS: The vertebral columns and attached thoracic walls were dissected from fresh porcine cadavers and used in the experimental surgery to evaluate the new system. As a next step, thoracoscopic surgery using this new system was performed on four or five vertebrae of five live pigs with an average weight of 50 kg. Initially, the discs and rib heads were removed through the thoracic wall. For each vertebra, a screw connected to a shaft used as a screw holder was inserted through the thoracic wall in a posterior to anterior direction. Each shaft then was linked outside the body to an outrigger. This outrigger was used to both create and restore scoliosis. A rod then was introduced through the thoracic wall and fixed to the screw heads. RESULTS: The animal experiments clearly showed that it was possible to change the Cobb angles of the spine through the use of the outrigger apparatus. In cadaver experiments, it was possible to create scoliosis and re-store it by 25 degrees to 35 degrees. Also, surgery on live pigs resulted in scoliosis of approximately 30 degrees, which means approximately 5 degrees to 10 degrees for each disc space. The procedures used also demonstrated that it was possible to fix a rod, introduced into the pleural cavity through a port, with screw heads. CONCLUSIONS: The use of this system successfully changed the Cobb angle of the spine, which suggests that its use should make it possible to correct spinal deformities. This apparatus also succeeded in fixing the rods in the screw heads, which raises the possibility of its use in spinal fixation. The authors believe that this apparatus could be adapted successfully for clinical use. Studies currently are under way in clinics using the new system.

Animals↗

PubMed2000

Estrogen deficiency is a potential cause for osteopenia in adult male patients with Noonan's syndrome.

Osteopenia is frequently observed in patients with Turner's syndrome. By contrast, there is no report concerning bone metabolism in patients with Noonan's syndrome which comprises Turner's phenotypic characteristics without any sex chromosome abnormalities. In the present investigation, we determined bone mineral density (BMD) as well as serum and urine indices of bone turnover in two male patients with Noonan's syndrome. Both patients showed remarkably decreased BMD, measured at two sites on the lumbar spine (L2-L4) and the distal end of the radius using dual energy X-ray absorptiometry (DXA). Urinary pyridinoline (PYD) and deoxypyridinoline (DPD) concentrations were significantly elevated in both patients, and serum osteocalcin and carboxyterminal propeptide of type I procollagen (PICP) concentrations were elevated in one patient. Surprisingly, both patients had a low level of serum 17beta-estradiol compared with control males, whereas they had normal levels of serum testosterone and dihydrotestosterone. Conjugated estrogens (Premarin 0.625 mg/day) were continued to be administered to these patients, followed up for 12 months. Urinary PYD and DPD concentrations gradually decreased, followed by an increase in their BMD. This is the first report that male patients with Noonan's syndrome showed osteopenia associated with increased bone resorption. Our data indicate that hypoestrogenism plays a potentially significant role in the abnormal bone metabolism in these patients.

Adolescent↗