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H Baba

Publications and source records attributed to H Baba.

At least 55 records · Page 3Linked to original sources
PubMed1997

Local spread of metastatic vertebral tumors. A histologic study.

STUDY DESIGN: Nineteen solitary metastatic vertebral tumors obtained by total en bloc spondylectomy were analyzed histologically. OBJECTIVES: To determine the mechanisms of local spread of vertebral tumors and identity barrier tissues to tumor progression in the vertebra. SUMMARY OF BACKGROUND DATA: Histologic studies of specimens resected at amputation or en bloc excision have determined the pattern of local spread of bone and soft tissue tumors in the extremities and identified barrier tissues to tumor spread. However, a similar assessment of vertebral malignancies is difficult. The development of total en bloc spondylectomy for primary vertebral malignancy and solitary has allowed the collection of tissue samples sufficient to analyze the pattern of local spread of tumors, using the concept of compartment and barrier. METHODS: Histologic sections of all vertebral elements were prepared from specimens collected after en bloc spondylectomy. Serial 5-mm sections in the sagittal plane were also prepared and examined. RESULTS: Analysis of tumor location showed that metastatic tumors reached the vertebral column by invading the bone marrow of the dorsal region of the vertebral body. The anterior longitudinal ligament, posterior longitudinal ligament, periosteum abutting the spinal canal, ligamentum flavum, periosteum of the lamina and spinous process, interspinous ligament, supraspinous ligament, cartilaginous endplate and the anulus fibrosus served as barriers to tumor progression. The posterior longitudinal ligament was the weakest barrier tissue and was gradually destroyed by the tumor at the point of perforating vessels. Even after destruction of the barrier tissue, tumor cells were covered with a thin, fibrous reactive membrane. Two pathways allowed tumor spread to the adjacent vertebrae: 1) from the edge of the vertebral body to the adjacent vertebral body beneath the longitudinal ligament, and 2) through the paravertebral muscles to the neighboring lamina. CONCLUSIONS: Each vertebra can be represented by a compartment surrounded by several barriers. The most common path for tumor spread is through the posterior longitudinal ligament to the epidural space.

Aged↗
PubMed1997

Total en bloc spondylectomy. A new surgical technique for primary malignant vertebral tumors.

STUDY DESIGN: The study of seven patients with primary malignant or benign aggressive tumors who underwent a new aggressive surgical technique termed "total en bloc spondylectomy" is reported. OBJECTIVES: To report a new surgical technique of total en bloc spondylectomy for complete, resection of primary spinal malignancy and for oncologic curability. SUMMARY OF BACKGROUND DATA: The conventional approach for primary spinal malignancy is via intralesional piecemeal resection, and very few reports have described en bloc extralesional resectioning with histopathologically wide or marginal surgical margins. METHODS: Total en bloc spondylectomy, consisting of en bloc laminectomy and en bloc corpectomy followed by anterior instrumentation with spacer grafting and posterior spinal instrumentation, was performed in five patients with primary malignant tumors and two patients with giant cell tumors. Patients were observed for 2 years to 6.5 years, except for one patient who died 7 months after surgery because of a mediastinal metastasis. RESULTS: All patients, except one, attained significant clinical improvement after surgery with no major complications. Histologically, the margins were wide or marginal except for the pedicles, and occasionally the spinal canal and the posterior, where they were accepted to be intralesional. One patient died of metastasis that was not directly related to surgery itself. There was no local recurrence. CONCLUSIONS: The advantages of total en bloc spondylectomy include resection of the involved vertebra(e) in two major blocs, rather than in a piecemeal pattern, and completion of the procedure during one surgical session posteriorly. The "total en bloc spondylectomy" offers one of the most aggressive modes of therapy for primary spinal malignancy.

Adolescent↗
PubMed1997

Vertebral lesions associated with palmoplantar pustulosis.

Spinal lesions were reviewed in 9 patients (3 men and 6 women) who presented with palmoplantar pustulosis. Cervical lesions were found in 3 patients and lumbosacral involvement in 7. The duration of disease averaged 4.8 years. Seven patients had associated sterno-costo-clavicular hyperostotic lesions, and all showed abnormalities in blood tests which suggested chronic inflammation. Vertebral lesions were assessed as a spondylodiscitis type in 4, single level syndesmophyte-forming type in 1, multiple hyperostosis type in 4, and an ivory vertebra type in 1. Five patients were treated conservatively, and 4 with progressive spondylodiscitis type lesions underwent curettage and anterior interbody fusions. At follow-up, all patients improved in both spinal and cutaneous presentations, and 4 who underwent surgery and 1 with tonsillectomy attained complete cure. The vertebral manifestations of palmoplantar pustulosis may vary, but rapidly progressive lesions need surgery for favourable early improvement from the vertebro-cutaneous symptom complex.

Female↗
PubMed1997

Stress fracture of the femoral component in total knee replacement: a report of 3 cases.

We report 3 cases of stress fracture of the femoral component (small size Whiteside Ortholoc II) in total knee replacements which occurred at 32, 52, and 73 months after operation. The site was at the junction between the medial posterior bevelled surface and the posterior flange. The most likely cause of failure is due to the thinness of the metal at this point.

Aged↗
PubMed1997

The tarsal tunnel syndrome: evaluation of surgical results using multivariate analysis.

Thirty-four patients with the tarsal tunnel syndrome were treated by decompression of the posterior tibial nerve. The condition was bilateral in 3 cases. There were 9 men and 25 women with an average age at operation of 41 years. The average follow up was for 3.8 years. Multivariate analysis showed that the outcome is influenced, in order of importance, by fibrosis around the nerve, the preoperative severity of the condition, a history of sprained ankle, worker's compensation, a long history, and heavy work. The results were favourable when there was a short history, the presence of a ganglion, no sprains, and light work. Measurement of the terminal latency of the medial plantar nerve was valuable in assessing recovery. The precise cause of the syndrome and its effect on treatment should be considered before operation.

Adolescent↗
PubMed1997

Three-dimensional topographic analysis of spinal accessory motoneurons under chronic mechanical compression: an experimental study in the mouse.

We investigated the effect of chronic mechanical compression of the cervical spinal cord on the number of spinal accessory motoneurons in 25 tiptoe-walking Yoshimura mice. The animals had calcified deposits in the atlantoaxial membrane at the C1-C2 vertebral level, compressing the spinal cord posterolaterally. Motoneurons of the spinal accessory nerve between C1 and C5 segments were labelled using wheat germ agglutinin-horseradish peroxidase (WGA-HRP) injected into the sternocleidomastoid muscles. The counted cells were processed into a three-dimensional computer display to analyse the cytoarchitectonic changes caused by external cord compression. The number of WGA-HRP-labelled spinal accessory motoneurons was significantly reduced on the affected side. The number of motoneurons in compromised C2 and C3 cord segments correlated linearly with the extent of mechanical compression, but no such relationship was present on the contralateral side. There was an increase in the number of WGA-HRP-labelled spinal accessory motoneurons in the medial cell pools of the anterior grey horn at a level most rostral to the compression, and in the ventrolateral cell pools at levels immediately rostral to the compression. Our findings suggest that the spinal accessory motoneurons translocate rostral to the area of external compression in order to avoid mechanical injury.

Animals↗
PubMed1997

Plasticity of the spinal cord contributes to neurological improvement after treatment by cervical decompression. A magnetic resonance imaging study.

To investigate the relationship between morphological plasticity of the spinal cord and neurological outcome after surgery for compressive lesions, we correlated the transverse area of the cervical spinal cord measured by transaxial magnetic resonance imaging (MRI) obtained during the early postoperative period (1-6 months) with neurological function assessed at a median postoperative follow-up period of 2.5 years. Measurements on MRI in 56 patients (35 men and 21 women) included evaluation of the cross-sectional area of the cervical cord and the subarachnoidal space at the level of decompression. The transverse area of the cervical cord increased by 30 to 62% postoperatively and that of the subarachnoidal space by 57 to 95%. Neurological improvement was noted in all patients and averaged 63% in our assessment scale. Expansion of the cervical cord during the early postoperative period correlated significantly with the late postoperative neurological status (P = 0.009). Our results suggest that an increase in the cross-sectional area of the cervical spinal cord, representing spinal cord morphological plasticity, is a significant factor in determining the late neurological improvement following decompressive surgery.

Adult↗
PubMed1997

Surgical treatment and outcome for node-negative gastric cancer.

BACKGROUND: The clinicopathologic characteristics and prognosis for patients with node-negative gastric cancer have heretofore remained to be determined. METHODS: We analyzed data on 730 of our patients with node-negative gastric cancer who underwent curative gastric resection in the Department of Surgery II, Kyushu University Hospital, between 1965 and 1990, with reference to prognostic factors. The presence of lymph node metastasis was determined by means of routine hematoxylin-eosin staining of excised tissues. RESULTS: The 5-year survival rate was 91.7% and the 10-year rate was 88.5%; thus the prognosis was good for patients with node-negative gastric cancer. When the prognosis was analyzed by stratification of each clinicopathologic factor, the survival time was shorter for older patients when the size of the tumor was larger, when the tumor involved the entire stomach, and when-tissues revealed infiltrative growth, serosal invasion, and lymphatic invasion. Extensive lymph node dissection was performed for 86.6% of the patients, and for these patients the prognosis was better, with a statistical difference. In a multivariate analysis, tumor size, serosal invasion, and extensive lymph node dissection proved to be independent prognostic factors for patients with node-negative gastric cancer. CONCLUSIONS: Prophylactic lymph node dissection for patients with gastric cancer will prolong the survival time.

Adult↗
PubMed1997

Regulation of vasomotion of arterioles and capillaries in the cat spinal cord: role of alpha actin and endothelin-1.

Ring-shaped vasoconstrictions of arterioles at their branching sites have often been reported in vascular corrosion casts of the brain and spinal cord in rats and cats. It is surmised that smooth muscle cells in arteriolar walls could regulate the blood flow by changing the diameter of the lumen (ie vasomotion). However, few reports have described vasomotion at the capillary (capillaries have no smooth muscle cells). Also, there have been no reports on endothelin-1 in the arterioles and capillaries of the spinal cord. This study was designed to determine (1) the electron microscopic architecture of vasomotion; (2) the immunohistochemical identification of alpha actin and endothelin-1 in the arterioles and capillaries of the spinal cord. Twenty-seven adult mongrel cats were used to study vascular corrosion casts at the lumbosacral spinal cord segments immunohistologically and through scanning electron microscopic observations. Sections of the spinal cord were stained with monoclonal anti-alpha actin and endothelin-1 antibodies. Vascular corrosion casts demonstrated two types of vasomotion: a sausage-like peristalsis and a ring-shaped vasoconstriction at the arteriole and capillary levels. In the immunohistological study, alpha actin and endothelin-1 were identifiable in the vascular wall at the bifurcation, and pericytes were found to contain microfilaments of alpha actin. The ring-shaped vasoconstriction might be regulated by smooth muscle cells in arterioles and by pericytes in capillaries by releasing endothelin-1.

Actins↗
PubMed1997

The epiconus syndrome presenting with radicular-type neurological features.

We report 15 patients with an epiconus syndrome presenting with radicular-type clinical features involving the lower extremities and identify the vertebral level at which the spinal cord terminated. All patients, consisting of 10 men and five women, aged 37 to 71 years, presented with unilateral or bilateral leg muscle atrophy as well as sensory deficit. Unilateral or bilateral reduction or absence of deep tendon reflexes were present in 13 patients, while pathological reflexes were seen in three cases and bladder dysfunction in 10. Prior to presentation, five patients with the epiconus syndrome were mistakingly diagnosed as having different spinal diseases, which were treated surgically. The level of epiconus compromise detected on radiological examination ranged from the lower level of the T10 vertebra to T12-L1 intervertebral disc level, but most frequently at T11-12 disc level. The level of termination of the spinal cord was between T12 and L1-2 disc level, but most frequently at the middle portion of the L1 vertebra, which was on average 1.6 +/- 0.4 (mean +/- standard deviation) vertebrae distal to the epiconus lesions. The presence of different neurological features related to epiconus compromise should be carefully examined with reference to the level of termination of the spinal cord.

Adult↗
PubMed1997

Ganglion cyst of the posterior longitudinal ligament causing lumbar radiculopathy: case report.

We describe a man aged 26 years who presented with a neurological syndrome, which was found on lumbar radioculopathy to be due to a ganglion cyst originating from the posterior longitudinal ligament. Based on MRI findings, cystic lesion was suspected, a round lesion at L4 level with no connection to the adjacent facet or to the dura matter. During surgery, a liquid-containing cystic lesion was found to originate from the posterior longitudinal ligament at L4 level. The resected cyst was diagnosed histologically as a ganglion cyst. A complete cure was established after surgery and no recurrence was noted at a follow-up 1.7 years postoperatively. A ganglion cyst of the posterior longitudinal ligament should be considered in the differential diagnosis of a cyst in the lumbar region causing neurological complications.

Adult↗
PubMed1997

Three-dimensional computed tomography for evaluation of cervical spinal canal enlargement after en bloc open-door laminoplasty.

We evaluated the use of three-dimensional (spiral) computed tomography (CT) to assess widening of the bony cervical spinal canal following en bloc open-door C3-C7 laminoplasty in 31 patients. Measurements were performed using a computerised image processing system. The increment in the anteroposterior spinal canal axis and volume of the bony spinal canal was investigated in relation to changes in cervical spine lordosis as well as postoperative neurological improvement. Neurological follow-up averaged 2.6 years (range, 1 to 7 years). A mean increase of 42% was observed in the anteroposterior axis of the canal between C3 to C7 after surgery, while the volume increased by 45%. Postoperatively, cervical spine lordosis correlated with increments in the volume of the enlarged bony canal rather than the anteroposterior axis. Postoperative neurological improvement correlated significantly with the increase in the canal volume. Our results indicate that spiral CT is useful for the assessment of the magnitude of cervical canal enlargement and evaluating the space available for the spinal cord following the relief of compression.

Adult↗
PubMed1997

Extraforaminal lumbar disc herniation at two contiguous intervertebral levels.

We describe two unusual surgical cases who presented with extraforaminal lumbar disc herniation that occurred at two adjacent vertebral levels simultaneously and unilaterally. Magnetic resonance imaging and selective nerve root infiltration followed by radiculography helped to outline the herniated disc material. Lateral fenestration and microsurgical foraminal widening of the affected vertebral levels allowed a complete and safe relief of the compressed nerves.

Female↗
PubMed1997

Potentiation of the cytotoxicity of carboquone by flavone acetic acid combined with hyperthermia.

Flavone acetic acid (FAA) has shown the effectiveness of vasoactive drugs in the selective reduction of tumor blood flow. A FAA-mediated decrease in tumor blood flow may produce sufficient hypoxic conditions within the tumor. Carboquone (CQ), a naturally occurring prototype bioreductive alkylating agent like mitomycin C (MMC), has been shown to be selectively more cytotoxic toward hypoxic tumor cells. We have reported enhancement of the combined antitumor effects of MMC plus FAA and hyperthermia (HT). In this study, we examined the combined effects of FAA, CQ and HT. In vitro, although HT (43 degrees C, 60 min) reduced the colonogenicity to 0.58 in CQ (0.01 microg/ml) alone, the combined cytotoxicity of CQ and HT was not enhanced with exposure to FAA at a concentration of 100 microg/ml. In vivo, the tumor growth time, calculated as the time required to reach twice the initial tumor volume, for CQ (2 mg/kg) alone, FAA (150 mg/kg) alone, CQ+FAA, CQ+HT (43 degrees C, 15 min), FAA+HT and FAA+CQ+HT was 6.1, 5.1, 7.1, 8.0, 7.6 and 13.4 days, respectively. A significant enhancement of antitumor effects by trimodality therapy with CQ, FAA and HT was observed, when compared to the treatment with CQ and FAA (p < 0.05). The possible mechanisms of an increased antitumor response achieved with the combination of CQ, FAA and HT may be explained in the following way: the FAA-mediated decrease in tumor blood flow produced sufficient hypoxic conditions within the tumor, and these resulted in a significant increase of the antitumor effects of CQ and HT.

Animals↗
PubMed1997

Use of osteonics UHR hemiarthroplasty for fractures of the femoral neck.

A clinical and radiographic study of bipolar hip arthroplasties was performed for fractures of the femoral neck. All patients were treated with the Osteonics UHR system. Clinical results were evaluated in 77 patients (77 hips) who were observed for an average of 4.8 years (range, 2-10 years). At the latest followup, 67 (87%) patients were rated as having a good or excellent outcome according to the Hospital for Special Surgery hip rating system. Clinical ratings in patients treated with cementless UHR were similar to or better than those of patients with cemented UHR. Hip dislocation occurred in only 3 (2.3%) patients, in whom the hip joint was reduced by a closed procedure without inducing disassembly of the prosthetic components. None of the patients had definitive acetabular erosion. The motion of the outer head was evaluated radiographically in 63 patients in weightbearing and non-weightbearing conditions, 3 to 108 months after surgery. The relative motion at the 2 sites of articulation of the outer head had stabilized by 3 months after surgery and subsequently remained unchanged. The authors' findings indicate that UHR hemiarthroplasty of the femoral head is a reliable treatment for fractures of the femoral neck.

Activities of Daily Living↗
PubMed1997

GFAP gene expression during development of astrocyte.

Glial fibrillary acidic protein (GFAP) is expressed exclusively in astrocytes in the central nervous system. In order to characterize individual cultured cells in which the GFAP promoter is active and to identify the regulatory mechanisms of GFAP expression in these cells, we have developed a unique assay system for promoter activity using retrovirus vectors. Retrovirus containing the mouse GFAP promoter fused to the lacZ gene were used to infect mixed glial cultures. The infected cells, in which the GFAP promoter was active, were visualized by X-Gal staining. From these experiments, we found that a 256 bp fragment 5' of the transcription initiation site was sufficient to confer astrocyte-specific expression of GFAP. The GFAP promoter became active about 3 days before GFAP protein can be detected immunohistochemically, which indicates that detection of GFAP promoter activity can be used to identify astrocyte progenitors. We have also established immortalized astrocyte cell lines in which we detect GFAP promoter activity. Immorto mouse is a transgenic mouse generated by the introduction of thermolabile SV40 T Ag, tsA58. A mixed glial culture prepared from 2-day-old Immorto mouse brain was incubated at 32 degrees C, at which temperature most of the cells expressed T Ag. The culture was then infected with retrovirus containing GFAP promoter-lacZ, and the infected cells were selected. Using the fluorescence-activated cell sorter with fluorescein di-beta-D-galactopyranoside as a substrate (FDG-FACS), these cells were separated into two groups: FDG(+), in which the GFAP promoter was active, and FDG(-), in which it was inactive. Mature astrocyte cell lines were established from the FDG(+) cells by colony isolation. The FDG(-) cells were cloned by colony isolation and cultured at 32 or 39 degrees C. At the latter temperature the expression of T Ag was suppressed and cell differentiation was induced in most cells. The cells which became positive for X-Gal staining only after switching to 39 degrees C were collected as immature astrocyte cell lines. These immortalized cell lines should be useful to investigate the molecular mechanisms of astrocyte differentiation.

Animals↗
PubMed1997

Astrocytic lineage analysis by detection of GFAP promoter activity in vitro.

To survey the emergence and onset of differentiation of the astrocytic lineage in the developing mouse cerebral wall, the promoter activity of a 2.5 kb 5'-flanking region of glial fibrillary acidic protein (GFAP) was measured in individual developing brain cells using a retrovirus-mediated gene transfer system. We identified precursors for astrocytes in primary culture of embryonic mouse cerebral wall cells by detection of GFAP promoter activity, which was detected approximately 3 days prior to the appearance of GFAP immunoreactivity. Since retroviruses only integrate into the chromosomes of actively proliferating cells, cells detected by this method should have been mitotically active at the time of retroviral infection on day 15 postfertilization (E15). Furthermore, we observed that cells activating GFAP promoter were located near the ventricular surface of cultured cerebral wall slices as a cluster of spherical cells. These results demonstrate that precursor cells for astrocytes exist within the germinative zone of developing cerebral wall, and that these cells are mitotically active on day E15, which is a late stage of neuronal production period in the mouse cerebral wall. The morphology, location and mitotic activity of these cells suggest that they are unlikely to be cells that have been transformed from radial glial cells.

Animals↗