Changes in the distribution of the control of the mitochondrial oxidative phosphorylation in regenerating rabbit liver

Applying the metabolic control theory, inhibitor titration studies were carried out on Complex I, III, IV, ATP synthase, ATP/ADP carrier and P(i) carrier of mitochondrial oxidative phosphorylation in normal and regenerating rabbit liver in order to examine the acceleration mechanism of mitochondrial oxidative phosphorylation. In regenerating rabbit liver the rate of state 3 respiration, respiratory control ratio and phosphorylation rate in the presence of mM glutamate, 250 microM ADP and 3 mM inorganic phosphate increased significantly as compared with the control by 73%, 48% and 76%, respectively. The control of the rate of state 3 respiration in normal liver was exerted by Complexes I, IV and steps other than the aforementioned six steps, whose flux control coefficients were 0.317, 0.214 and 0.469, respectively. By contrast, in regenerating liver, the control was more evenly distributed among these steps in oxidative phosphorylation and the possibility is suggested that Complexes I, IV and steps other than the six steps are activated during regeneration. The activation of Complexes I and IV was attributed to their increased activity, since it was not accompanied by an increase in the amount of the enzymes.

Retinoids (all-trans and 9-cis retinoic acid) stimulate production of macrophage colony-stimulating factor and granulocyte-macrophage colony-stimulating factor by human bone marrow stromal cells

Retinoic acids (RAs) exert pleiotropic effects on cellular growth and differentiation. All-trans retinoic acid (ATRA) and 9-cis retinoic acid (9-cis RA), a stereoisomer of ATRA, induce differentiation of leukemic cell lines and cells from patients with acute myelogenous leukemia (AML) in vitro. Despite information on the effects of RAs on hematopoietic cells, little is known about how RAs act on the hematopoietic microenvironment, especially on bone marrow stromal cells. Based on recent observations that various cytokines produced mainly by bone marrow stromal cells regulate hematopoiesis, we analyzed the effects of RAs on cytokine production by these cells. ATRA or 9-cis RA treatment of human bone marrow stromal cell line KM101, which produces macrophage colony-stimulating factor (M-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) constitutively, enhanced mRNA levels of both cytokines in a dose-dependent manner. Both RAs also stimulated M-CSF production from primary cultures of human bone marrow stromal cells. Both retinoic acid receptor (RAR)-alpha and retinoid X receptor (RXR)-alpha were expressed constitutively in KM101 cells. ATRA did not affect the expression of either receptor, whereas 9-cis RA increased RXR-alpha mRNA expression in a dose-dependent manner, but did not affect levels of RAR-alpha mRNA. These findings may have important biologic implications for both the role of RAs in hematopoiesis and the therapeutic effects of ATRA on the hematopoietic microenvironment in patients with acute promyelocytic leukemia (APL).

Brain activation study by use of positron emission tomography in unanesthetized monkeys

A system for the measurement of brain activity in conscious monkeys by positron emission tomography (PET) was established in the present study. The signal/noise ratio was maximal around 40 s for data acquisition in the PET scan with 15O-labeled water. When the monkey was stimulated by vibration and subtraction images of the data sets from regional cerebral blood flow (rCBF) changes in paired stimulation and control were superimposed on magnetic resonance images obtained from the same specimens, a somatotopic map corresponding to the sites stimulated was clearly demonstrated. Visual stimulation with a photic stimulator activated the corresponding regions of the primary visual cortex. Comparison of the activated sites and extents under the conscious state with those under anesthesia assured that the study is controllable; there was little unpredictable activation due to unlimited subject movement or to psychological effects.

A naturally occurring single basic amino acid substitution in the V3 region of the human immunodeficiency virus type 1 env protein alters the cellular host range and antigenic structure of the virus

Human immunodeficiency virus type 1 circulates in vivo as a mixture of heterologous populations (quasispecies). We previously analyzed the quasispecies of the third hypervariable region (V3) in the viral envelope glycoprotein gp120 in an infected individual and found that the species with a basic amino acid substitution (lysine for aspartic acid) at a particular position evolved and became a distinct population within a short period, followed by progression to the typical immunodeficiency stage (S. Oka et al., AIDS Res. Hum. Retroviruses 10:271-277, 1994). In the present study, we examined the biological significance of this amino acid substitution by constructing recombinant viruses with specific point mutations and comparing their replication capabilities in different cell types. The results demonstrated that the single basic amino acid substitution was sufficient to render a virus fully capable of replicating in human T-cell lines under certain conditions. With an acidic amino acid at the position, the virus grew much less fast or did not grow at all in the T-cell lines. Viral neutralization assay and peptide enzyme-linked immunosorbent assays further showed that this amino acid substitution resulted in different recognition by several of the serum specimens from human immunodeficiency virus type 1-infected individuals and thus could alter the antigenic structure. An additional finding worthy of note was that at the terminal stage, the proviral sequences of peripheral blood mononuclear cells and the viral isolates from them were without exception of the late type with the basic amino acid substitution, whereas the early sequence without the substitution was retained as a major subset in the spleen. These results support the notion that basic amino acid substitutions in V3 are a strong predictor of virus tropism and may be relevant to disease progression.

Biological characteristics of a continuous cultured cell line derived from a human malignant fibrous histiocytoma

A continuous cultured cell line, NATO, was established from a human malignant histiocytoma of bone. The cultured cells consisted of at least 3 types of tumor cells; polygonal, long spindle and occasionally giant cells, which were primarily observed in the original tumor of the patient. Ultrastructurally, they were mostly immature cells that had poorly developed cell organelles and a few lysozomal granules. The cultured cells had phagocytotic activity and were positive for acid phosphatase, transferrin receptor, alpha 1-antitrypsin, alpha-naphthyl acetate esterase and HLA-DR, but negative for Fc- and C3-receptors. Allotransplantation of the cells into athymic nude mice produced tumors at early passages, but did not 3 years later. Four cloned sublines isolated from the parent line also showed essentially an identical morphology with that of the parent cell line, indicating that the 3 cell types were interchangeable.

Diagnosis of t(2;5)(p23;q35)-associated Ki-1 lymphoma with immunohistochemistry

Some Ki-1 lymphomas carry a specific chromosomal translocation, t(2;5)(p23;q35). We have recently found a novel hyperphosphorylated 80-kD protein tyrosine kinase, p80, in a human Ki-1 lymphoma with this translocation. Subsequent cDNA cloning showed that p80 is a fusion protein of two different genes on chromosome 2p23 and 5q35, the novel tyrosine kinase gene and nucleophosmin gene, respectively. In this study, we intended to detect p80 on lymphoma tissues with immunologic methods. Thus, we developed rabbit polyclonal antibody using a synthetic peptide corresponding to a part of its kinase domain. The antibody (anti-p80) immunoprecipitated and immunoblotted p80 specifically from AMS3. Then, to examine whether t(2;5)(p23;q35) was present on biopsied lymphomas, reverse transcriptase-polymerase chain reaction (RT-PCR) covering the fusion junction of p80 mRNA was performed. Among 10 Ki-1 lymphomas and 10 additional lymphomas other than the Ki-1 lymphomas, expression of p80 mRNA was detected in three cases exclusively. When these 20 cases and additional 30 lymphomas were immunostained with anti-p80, positive staining was noted exclusively in the three cases found by PCR to have harbored the p80 mRNA. Thus, the present immunostaining, as well as PCR, was shown to be efficient for detecting lymphomas producing this chimeric protein/mRNA.

Aleutian mink disease: puzzles and paradigms

Aleutian mink disease (AD) is a naturally occurring persistent virus infection of mink caused by the Aleutian mink disease parvovirus (ADV). The classical form of AD, which occurs in adult mink, is notable for high titers of antiviral antibodies, hypergammaglobulinemia, plasmacytosis, and immune complex disease. In addition, there is a progressive renal disease characterized by mesangial proliferative glomerulonephritis and severe interstitial nephritis. Development of AD depends on both host and viral factors, and mink of certain genotypes fail to develop progressive disease when inoculated with low-virulence strains of virus. In newborn mink kits, ADV causes a fatal, acute interstitial pneumonitis associated with permissive viral replication in alveolar type 2 cells, but treatment of newborn kits with anti-viral antibody aborts the acute disease and converts into one resembling the persistent infection observed in adults. In infected adult mink, ADV is sequestered as immune complexes in lymphoid organs, but actual viral replication is restricted at the level of the individual cell and can be detected in only a small population of macrophages and follicular dendritic cells. ADV infection of mink primary macrophages and the human macrophage cell line U937 is antibody dependent and leads to the production of the cytokine interleukin-6. Furthermore, levels of interleukin-6 are increased in lymph node culture supernatants from infected mink. Chronic production of interleukin-6 may promote development of the immune disorder characteristic of AD.

Rearrangement of bcl-2 is detectable in Hodgkin's disease by polymerase chain reaction

The authors examined the occurrence of the t(14;18) chromosomal translocation in 44 cases of Hodgkin's disease (HD) using the polymerase chain reaction and Southern blot hybridization with non-radioactive oligonucleotide probes. DNAs were extracted from unfixed, fresh-frozen and formalin-fixed, paraffin-embedded biopsy specimens. Southern blot hybridization of the amplification product showed that, of 44 HD DNAs, three had a detectable t(14;18) breakpoint at the mbr (major breakpoint region), while none had a detectable t(14;18) breakpoint at the mcr (minor cluster region). Of the three cases positive for a t(14;18) breakpoint at the mbr, two were of lymphocyte predominance type, and the other was of mixed cellularity type.

Multi-segmental and generalized suppression of postural muscle tone evoked by stimulating the dorsal tegmental field and the medial pontine reticular formation in acute decerebrate cats

In acute decerebrate cat, stimulation of the dorsal tegmental field (DTF) of the caudal pons along its midline and the medial pontine reticular formation (mPRF) evokes generalized suppression of postural muscle tone. In this study, the effects of stimulation of the DTF area were compared with those evoked by stimulating the mPRF unilaterally or bilaterally. By stimulating the mPRF bilaterally, simultaneous suppression of tonic activities in the neck, lumbar back, forelimb and hindlimb muscles, bilaterally, was evoked as that evoked by stimulating the DTF area alone.

Etretinate administration reduces serum propeptide of type I procollagen level in patients with psoriasis

The serum carboxyterminal propeptide of type I procollagen (PICP) level in 26 patients with psoriasis was significantly lower than in control subjects (124 +/- 47 and 224 +/- 78 ng/ml, respectively; P < 0.001). The patients were divided into two groups, those treated with etretinate and untreated patients. PICP levels in the treated group were significantly lower than those in the untreated group (P < 0.001), but there was no difference between the control and untreated groups. In addition, there was a negative correlation between PICP levels and the serum etretinate concentration in treated patients (r = -0.622, P < 0.05). There was no difference between procollagen type III aminoterminal propeptide (PIIIP) levels in patients and controls, nor was there any significant difference between etretinate-treated and untreated patients. In cell culture studies, etretinate dose-dependently (from 10(-9) to 10(-5) M) decreased the PICP concentration in the medium of fibroblasts from both healthy subjects and patients. In osteoblast cell culture, PICP levels were reduced only in a high concentration of etretinate (10(-5) M). However, no change was observed in preadipose cells. Our in vivo and in vitro observations indicated that psoriasis per se did not affect either serum PICP or PIIIP levels, but that etretinate had an inhibitory effect on collagen synthesis by fibroblasts. Hence, the administration of etretinate to psoriatic patients is, at least in part, responsible for the reduction of serum PICP levels in these patients.

[Late phase II clinical study of RP56976 (docetaxel) in patients with advanced/recurrent breast cancer]

A late phase II clinical study of RP56976 (Docetaxel), a new semisynthetic anticancer agent, was conducted in patients with advanced/recurrent breast cancer. RP56976 (Docetaxel) was in general administered at an intravenous dose of 60 mg/m2 with dose-free intervals of 3-4 weeks. Of the 74 patients enrolled, 64 patients completed the scheduled course of treatment. Three patients showed complete response (CR), 32 patients partial response (PR), 3 patients minor response (MR), 18 patients no change (NC), and 8 patients had progressive disease (PD). The overall response rate was 54.7%. The response rate in patients who previously had received chemotherapy was 55.7%, and the response rate in patients who had resistance to anthracycline agents or who did not respond to previous treatment was 58.7%. Adverse reactions included nausea/vomiting in 38 patients (57.6%), fatigue in 46 patients (69.7%), anorexia in 46 patients (69.7%), fever in 26 patients (39.4%), and alopecia in 60 patients (90.9%), all of which were tolerable. Abnormal laboratory findings included leukopenia (Grade III or more) in 57 patients (86.4%) and neutropenia (Grade III or more) in 56 patients (86.2%). The results show that RP56976 (Docetaxel) is an excellent agent with high antitumor effect for the treatment of advanced/recurrent breast cancer.

Adenovirus pulmonary infections identified by PCR and in situ hybridisation in bone marrow transplant recipients

AIMS

To investigate adenovirus pulmonary infections in bone marrow transplant (BMT) recipients.

METHODS

Formalin fixed, paraffin wax embedded lung tissue was examined from 13 necropsy cases after BMT using PCR and in situ hybridisation to detect adenovirus DNA. The E1A region of the adenoviral genome was targeted for PCR. In situ hybridisation was performed only in the PCR positive cases.

RESULTS

Of the 13 lung specimens analysed, nine cases were negative for adenoviral nucleic acid. Four (30%) PCR and two (15%) in situ hybridisation positive cases were found. In some of the patients there were clinical and pathological indications that some diseases might be associated with adenovirus infection--haemorrhagic cystitis (three cases); necrotising pneumonia (one case). In necrotising pneumonia in which no pathogenic agents had been shown by conventional histological study, the in situ hybridisation technique showed positive staining for adenovirus. In a patient who died of renal failure caused by adenovirus nephritis, both PCR and in situ hybridisation were positive in the lung as well as in the kidney, although no histological change was found. Two PCR positive cases lacked positive sites for adenovirus by in situ hybridisation.

CONCLUSIONS

The combination of PCR and in situ hybridisation could be useful for diagnosing adenovirus infection of the lung in BMT recipients. These results provide a basis for exploring further the clinical use of PCR and in situ hybridisation to diagnose adenovirus infection.

Antibody-binding to the 180-kD bullous pemphigoid antigens at the lateral cell surface causes their internalization and inhibits their assembly at the basal cell surface in cultured keratinocytes

We demonstrated the effects of monoclonal antibodies to the 180-kD and 230-kD BP antigens (BPA) and of BP sera on Ca(++)-induced formation of hemidesmosomes in cultured human keratinocytes (a cell line, DJM-1) by immunofluorescence microscopy. Under low Ca++ (0.07 mM) conditions, the 180-kD and 230-kD BPAs were distributed homogeneously on the basal plasma membrane, while they formed a peculiar concentric ring or arch (ring/arch) arrangement in high-Ca++ (1.87 mM) medium. On the other hand, the apical-lateral cell membrane was stained homogeneously with antibodies to the 180-kD BPA, but not to the 230-kD BPA, both in low and high Ca++ media. The low-high Ca++ switch at first caused disappearance of the antigen from the basal plasma membrane and then formed the high-Ca++ ring/arch pattern within 3 hrs. In this system, monoclonal antibodies to the 180-kD and 230-kD BPAs and the sera from 5 BP patients, 2 pemphigus vulgaris (PV) patients, and 4 normal volunteers were added into the culture media. The addition of anti-180-kD BPA antibodies or any BP serum caused the internalization of the 180-kD BPA from the apical-lateral cell membrane and inhibited the Ca(++)-induced formation of the ring/arch pattern on the basal membrane, possibly by inhibiting the movement of the antigen from the lateral to the basal membrane to form hemidesmosomes.(ABSTRACT TRUNCATED AT 250 WORDS)

Accumulation of genetic alterations during esophageal carcinogenesis

Using polymerase chain reaction amplification of microsatellite regions in DNA from 11 epithelial dysplasias of the esophagus and 21 early squamous cell carcinomas, we were able to detect frequent loss of heterozygosity (LOH) on chromosomes 3p21.3 and 9q31 even in low-grade dysplasias. In contrast, we observed frequent LOHs on chromosomes 9p22 and 17p13 (TP53 locus) only in high-grade dysplasias and carcinomas, but not in any low-grade dysplasias. Analysis of LOH at the same four chromosomal regions in DNA of five additional minimal carcinomas and accompanying dysplastic lesions revealed loss of alleles at the loci on 3p21.3 and 9q31 throughout various degrees of dysplasia and carcinoma; again, LOHs on 9p22 and 17p13 occurred only in high-grade dysplasia and carcinoma in situ. Our results indicated that inactivation of putative tumor suppressor genes on 3p21.3 and 9q31 may be early genetic events during esophageal carcinogenesis, and that additional genetic alterations on 9p22 and 17p13 probably play roles in progression.

Giant symptomatic myelolipoma of the adrenal gland

A case of giant symptomatic myelolipoma is described in which clinical differentiation was difficult. It was considered to be an extremely rare case of giant myelolipoma arising in the adrenal gland. Histologically the present case contained more lipomatous elements than others reported to data. This is a case of giant adrenal myelolipoma with a few foci of myeloid elements and it is suggested that this case has a true neoplastic nature rather than a hyperplastic or metaplastic one.

Imaging features of maxillary osteoblastoma and its malignant transformation

We report two cases of osteoblastoma, one of them an unusual case in a 32-year-old woman in whom a maxillary tumor was confidently diagnosed as an osteoblastoma at the time of primary excision and subsequently transformed into an osteosarcoma 7 years after the onset of clinical symptoms. The other patient developed osteosarcoma arising in the maxilla, which was diagnosed 3 years after the primary excision and is very suggestive of malignant transformation in osteoblastoma. We present the radiological features, including computed tomographic and magnetic resonance imaging studies, of this unusual event of transformed tumor and compare imaging features of benign and dedifferentiated counterparts of this rare tumor complex.

OLETF (Otsuka Long-Evans Tokushima Fatty) rat: a new NIDDM rat strain

The characteristic features of OLETF rats are: (1) late onset of hyperglycemia (after 18 weeks of age); (2) a chronic course of disease; (3) mild obesity; (4) clinical onset of diabetes mellitus (DM) mostly in males; (5) hereditary trait: (a) multiple recessive genes are involved in the induction of DM; (b) rat MHC, RT1 has no diabetogenic effect; (c) control strain, LETO appears to share some of diabetogenic genes with OLETF rats; (d) female OLETF rats also carry diabetogenic genes; and (e) one of the diabetogenic genes, designated as odb-1, is transmitted linked with the X-chromosome of OLETF rats, however testosterone is an important factor involved in developing diabetes; (6) the changes of pancreatic islets can be classified into three stages: (1) an early stage (at less than 9 weeks of age) mild lymphocyte infiltration; (2) a hyperplastic stage (10-40 weeks of age); hyperplastic change and fibrosis in or around islets; (3) a final stage (at more than 40 weeks of age) showing atrophy of islets; (7) diabetic nephropathy; (a) diffuse glomerulosclerosis; (b) nodular lesion (thickening of basement membranes, mesangial proliferation, fibrin cap). These clinical and pathologic features of disease in OLETF rats resemble those of human NIDDM.

DNA ploidy in human esophageal squamous dysplasias and squamous cell carcinomas as determined by image analysis

The DNA content in cells from 98 sites from 14 surgical specimens of human esophageal carcinoma, including nonpathologic epithelium; mild, moderate, and severe squamous dysplasia and squamous cell carcinoma; and in cells from 13 sites from 13 noncancerous biopsy specimens, including nonpathologic epithelium and mild and moderate dysplasia, was determined in Feulgen-stained sections by the cell analysis system (CAS 200). In surgical specimens, diploid DNA histogram patterns were observed in 16 of 17 nonpathologic epithelia, two of seven mild dysplasias, 12 of 21 moderate dysplasias, nine of 18 severe dysplasias, six of 12 intraepithelial carcinomas, and nine of 22 advanced carcinomas. In biopsy specimens, diploid patterns were observed in four of four nonpathologic epithelia, two of seven mild dysplasias, and two of two moderate dysplasias. The remaining displayed nondiploid patterns. There was a statistically significant difference in the frequency of nondiploid histogram between nonpathologic epithelium and pathologic esophageal lesions, including squamous dysplasia and carcinoma in both surgical and biopsy specimens, but not between squamous dysplasia and carcinoma in surgical specimens. We found statistically significant differences in some parameters, including the population of cells in S-phase fraction, diploid fraction, tetraploid or higher chromosome content, and peak cell number, between nonpathologic epithelium and pathologic esophageal lesions demonstrating diploid histograms. In contrast, there were no significant differences between squamous dysplasia and carcinoma demonstrating diploid histogram in those five parameters described above.(ABSTRACT TRUNCATED AT 250 WORDS)

[Idiopathic interstitial pneumonia that responded to intermittent intravenous administration of high-dose cyclophosphamide]

A 78-year-old man was admitted to the hospital with exertional dyspnea and fever. Chronic idiopathic interstitial pneumonia (IIP) had been diagnosed a year before. Follow-up chest X-ray examination showed diffuse reticular shadows and progressive shrinkage of both lower lobes. Chest CT scan revealed honeycomb appearance of both lower lung fields. Moderate hypoxemia was found by arterial blood gas analysis. The patient responded to an orally administered corticosteroid. Because tapering of the medicine caused exacerbation of the hypoxemia, methylprednisolone pulse therapy was given with poor response. Then high-dose (750 mg) of cyclophosphamide (CPM) were given intravenously 6 times, every 3 or 4 weeks. After the second administration of CPM, decreases in hypoxemia and in blood LDH levels were observed. This treatment allowed as to taper the dose of oral corticosteroid from 60 mg/day to 15 mg/day. This case suggests that intravenous administration of high-dose CPM may be effective against IIP.

Living related liver transplantation across ABO blood groups

We performed 13 pediatric liver transplants from ABO-incompatible living related maternal or paternal donors using a combination of preoperative removal of isohemagglutinin and postoperative immunosuppressive therapy with FK506 and prophylactic OKT3. Tissue near-infrared spectroscopy was applied to evaluate hemodynamics using the hemoglobin of red cells in the sinusoids as an index. The data obtained indicated that the preoperative removal of isohemagglutinin prevented hyperacute humoral rejection with hemorrhagic infiltration in the sinusoids in 10 successful cases. The incidence of acute rejection was not significantly different among ABO-identical, -compatible, and -incompatible groups. The estimated 1-year survival rate of the ABO-incompatible group was 77%.

Iron Inefficiency in Maize Mutant ys1 (Zea mays L. cv Yellow-Stripe) Is Caused by a Defect in Uptake of Iron Phytosiderophores

To determine the Fe inefficiency factors in the maize mutant ys1 (Zea mays L. cv Yellow Stripe), root exudates of Fe-inefficient ys1 and of two Fe-efficient maize cultivars (Alice, WF9) were collected in axenic nutrient solution cultures. Analysis by thin-layer chromatography and high-performance liquid chromatography revealed that under Fe deficiency ys1 released the phytosiderophore 2[prime]-deoxymugineic acid (DMA) in quantities similar to those of Alice and WF9. Under nonaxenic conditions, DMA released by plants of all three cultivars was rapidly decomposed by microorganisms in the nutrient solution. Uptake experiments with 59Fe-labeled DMA, purified from root exudates of either Fe-deficient Alice or ys1 plants, showed up to 20 times lower uptake and translocation of 59Fe in ys1 than in Alice or WF9 plants. The presence of microorganisms during preculture and short-term uptake experiments had no significant effect on uptake and translocation rates of 59Fe in Alice and ys1 plants. We conclude that Fe inefficiency in the maize mutant ys1 is the result of a defect in the uptake system for Fe-phytosiderophores.

Nutritional support through percutaneous transhepatic internal drainage route in common bile duct cancer

A 69 year old female with a duodenal bulb obstruction due to direct invasion of common bile duct cancer who received total enteral nutrition through the route of percutaneous transhepatic internal drainage (PTID) was presented. The tip of PTID tube was placed over the duodeno-jejunal flexure. Jejunal infusion of all nutrients and the bile juice through this route kept her in good nutritional condition until the terminal stage of primary disease. This procedure did not cause the infection of the biliary system. Major problems, tube obstruction and diarrhoea, were easily resolved with the selection of an appropriate infusion schedule and nutrient concentration. We conclude that nutritional support through the PTID route is a beneficial means for compromised patients without laparotomy or hospitalization.

[Burst fracture: osteoporotic vertebral compression fracture associated with paraplegia]

It is rare that vertebral compression fracture of senile osteoporosis causes paraplegia. This article reviews 164 cases reported in Japan since 1974. These fractures were characterized as follows: 1) paraplegia occurred in elderly females (average 69.3 years old) with severe osteoporosis, 2) traumatic histories were revealed in 52%, 3) 91% of the fractures were classified into burst type, 4) location was in the thoracolumber region (80.5%), 5) average onset of paraplegia was 5.7 months after fracture. One hundred and twenty nine cases were surgically treated either by anterior vertebral fusion or by posterior instrumentation and 35 cases were conservatively treated. Surgical cases showed better recovery of walking ability than conservative cases.