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T Sakai

Publications and source records attributed to T Sakai.

At least 19 recordsLinked to original sources
PubMed2006

I.V. infusion of a drag-reducing polymer extracted from aloe vera prolonged survival time in a rat model of acute myocardial ischaemia.

BACKGROUND: I.V. infusion of drag-reducing polymers (DRPs) has been shown to improve survival time in animals subjected to haemorrhagic shock. We hypothesized that DRPs might prolong survival time in rats following acute myocardial ischaemia (AMI). METHODS: Sixteen adult male rats were anaesthetized and mechanically ventilated. An i.v. infusion of either Dextran-40 2.5% (Control, n=8) or Dextran-40 2.5% containing 50 microg ml(-1) of an aloe vera-based DRP (DRP, n=8) was initiated at 3.5 ml h(-1). The left anterior descending coronary artery was ligated. Blood pressure, skin-tissue perfusion, and heart rate were monitored and arterial blood samples were analysed. RESULTS: The mortality at 60 min following coronary ligation was 0% in the DRP group vs 50% in the control group (P=0.025). DRP-treated animals maintained higher mean arterial pressure [60.9 (5.1) vs 47.5 (5.1) mm Hg, P=0.004] and tissue perfusion [4.2 (3.4) vs 1.2 (0.5) TPU, P=0.029]. The DRP group trended towards better acid-base status with base excess [-5.0 (1.7) vs -8.1 (5.1) mmol litre(-1), P=0.083] and pH [7.42 (0.07) vs 7.35 (0.02), P=0.03]. CONCLUSIONS: Administration of nanomolar concentrations of aloe vera-based DRP prolonged survival time in animals with AMI. DRPs may offer a novel method to treat organ/tissue hypoperfusion.

Acute Disease↗
PubMed2006

Molecular epidemiology of rabies from Maranhão and surrounding states in the northeastern region of Brazil.

Although many outbreaks of rabies have been reported in northern Brazil, few epidemiological studies of these outbreaks have been undertaken. In this study, molecular epidemiological analyses were performed using 41 rabies virus samples isolated in the Maranhão (MA), Pará (PA), and Tocantins (TO) states of northeastern Brazil. A 599-bp region of the glycoprotein (G) gene was first amplified from each sample by RT-PCR, then sequenced and subjected to phylogenetic analysis. A phylogenetic tree divided the 41 isolates into two clades: Clade I was associated with terrestrial carnivores and Clade II was associated with vampire bats. The Clade I isolates were further sub-divided into two groups. The first group was closer to carnivore isolates that predominate in central Brazil, whereas the second group more closely resembled wild fox isolates from the northeastern coastal state of Paraíba (PB). MA isolates of Clade II formed an entirely separate group. These results demonstrate that bat- and dog-transmitted rabies occur in northwestern Brazil.

Animals↗
PubMed2006

Preservation of C7 spinous process does not influence the long-term outcome after laminoplasty for cervical spondylotic myelopathy.

Axial pain is one of the major complications after laminoplasty, and preservation of C7 spinous process during the procedure can reduce the axial pain. However, it has not been elucidated whether laminoplasty preserving the C7 spinous process can maintain neurological improvement for a long time. The purpose of our retrospective study was to investigate the long-term neurological outcome after open-door laminoplasty preserving the C7 spinous process for cervical spondylotic myelopathy (CSM). Clinical and radiological outcomes were analysed in 42 patients who underwent open-door laminoplasty preserving C7 spinous process and followed up for more than 5 years. Neurological function was evaluated by means of the Japanese Orthopaedic Association (JOA) scoring system for cervical myelopathy. Axial pain was assessed using a visual analog scale (VAS) at the last examination. Alignment and motion of the cervical spine were measured from radiographs, and magnetic resonance imaging (MRI) was used to evaluate postoperative compression at C7. The mean JOA score was 9.4 before surgery and 12.0 at the latest follow-up. The mean VAS score in 26 patients score was 9.7/100. No compression of the spinal cord was observed in any MRI at the latest follow-up. Preservation of the C7 spinous process does not influence the long-term outcome of CSM after laminoplasty. Although we did not have a comparative group, the procedure described here should be considered as the solution.

Adult↗
PubMed2006

[New CT program simulating kidney displacement during retroperitoneal laparoscopic nephrectomy].

A total of 12 patients with malignant localized renal or ureteral neoplasms underwent multi-slice computed tomography. Imaging data were sent to the dedicated workstation to create volume rendering and virtual laparoscopic images of the kidney which was displaced ventrally with retroperitoneal balloon. These findings were compared with video images obtained during retroperitoneal laparoscopic nephrectomy. The kidney displacement simulator depicted all renal arteries (100% sensitivity) and 13 of 14 renal veins (93% sensitivity). Hilar anatomy, including the tumor, major vessels and their relationships were visualized as in the actual laparoscopic views. The desired portions of major vessels as well as the left adrenal and gonadal veins visualized with this system completely corresponded with the actual laparoscopic images during surgery. The kidney displacement simulator is useful to foresee desired portions of major vessels and branched small vessels such as the adrenal or gonadal veins in advance of surgery. It is thus able to guide surgeons and reduce operative risks and possible complications.

Catheterization↗
PubMed2006

The alpha2 type IX collagen tryptophan polymorphism is associated with the severity of disc degeneration in younger patients with herniated nucleus pulposus of the lumbar spine.

Tryptophan alleles in COL9A2 (Trp2) and COL9A3 (Trp3) have been linked to lumbar disc diseases in the Finnish population. Although such diseases consist of various pathogenetically different conditions, detailed analysis of each has not been well documented. The aim of this study was to clarify whether the collagen IX tryptophan alleles influence the symptomatic degeneration of the lumbar disc in Japanese patients with herniated nucleus pulposus. We performed a prospective study of 84 patients who underwent lumbar discectomy. The degree of disc degeneration was evaluated by magnetic resonance images in relation to the collagen IX genotype. Twenty patients (21.4%) had the Trp2 allele and no patients had the Trp3 allele. Patients under 40 years with the Trp2 allele showed more severe disc degeneration at the surgical level than did those without the Trp2 allele (odds ratio 6.00, P=0.043). In contrast, patients aged 40 years or over did not show significant association between disc degeneration and collagen IX genotype. Our results suggest that the Trp2 allele is an age-dependent risk factor for the severity of disc degeneration in younger patients with symptomatic herniated nucleus pulposus of the lumbar spine.

Adult↗
PubMed2006

Spindle cell metaplasia arising in thyroid adenoma: characterization of its pathology and differential diagnosis.

Spindle cell metaplasia in thyroid adenoma or carcinoma is rare and its pathological features are not well characterized. Distinction of this entity from medullary or anaplastic carcinoma has an important clinical implication. We encountered a case of thyroid follicular adenoma associated with spindle cell metaplasia. It showed "tumor in tumor appearance" and neoplastic spindle cells were positive for thyroglobulin, thyroid transcription factor-1, vimentin and focally chromogranin A and somatostatin (SS). MIB-1 index was <1%. Ultrastructure of the spindle cells was reminiscent of follicular cell origin. From the findings from our case, spindle cell metaplasia appears to be a benign clinical entity, suggestive of multidirectional differentiation of follicular cells.

Adenoma↗
PubMed2006

The clinical significance of cerebrospinal fluid lipid peroxides in central nervous system disease.

Forty-four dogs were referred to our hospital presenting with neurological symptoms such as seizure or paraparesis. Magnetic resonance imaging (MRI) revealed abnormal results in 21 (abnormal MRI group) and normal results in 23 dogs (normal MRI group). Cerebrospinal fluid (CSF) (normal MRI group, n = 22; abnormal MRI group, n = 21) and serum lipid peroxide (LP) concentrations (normal MRI group, n = 11; abnormal MRI group, n = 15) were measured in a number of these dogs, and revealed a significant difference in the CSF/serum LP values (normal MRI group, n = 10; abnormal MRI group, n = 14) between the abnormal and the normal MRI groups (t-test and Mann-Whitney U-test p < 0.05). No other significant differences were observed. CSF/serum LP values exceeding 1.0 were exhibited in 10 of 14 dogs (71%) in the abnormal MRI group, and in 1 of 10 dogs (10%) in the normal MRI group. In the remaining animals, 4 dogs of the abnormal MRI group showed CSF/serum values lower than 1.0, 3 dogs had morphological abnormalities but no abnormal MRI signals in the central nervous system, and 1 dog had an abnormal MRI signal but no pathological abnormality. In the CSF analysis, 3 of 16 dogs (19%) of the abnormal MRI groupshowed abnormal cell counts and/or protein content. We conclude that the CSF/serum LP value can be used for the detection of neurological lesions such as oedema, inflammation and tumour.

Animals↗
PubMed2006

Intraperitoneal injection of oxygenated perfluorochemical improves the outcome of intraportal islet transplantation in a rat model.

A 50% to 75% early graft loss upon engraftment has been suggested to in intraportal islet transplantation (IPIT). Hypoxia in the portal vein contributes to graft loss in immediately posttransplantation. Herein we examined the effect on the outcome of IPIT of intraperitoneal oxygenated perfluorochemical (PFC) as an oxygen carrier. Isolated Lewis rat islets were transplanted into the portal vein of a chemically induced diabetic syngeneic rat. First, 1500 IEQ was determined to be the optimal dose in this study. When oxygenated PFC (group 1) was intraperitoneally injected following IPIT of 1500 IEQ, the success rate of transplantation was 5/6, in contrast to 1/6 when PFC with no oxygen was injected (group 2) and 1/6 in IPIT without PFC, respectively. The area under the glucose profile curve on intraperitoneal glucose tolerance tests on posttransplant day 28 in group 1 was significantly smaller than that for group 2. In conclusion, intraperitoneal oxygenated PFC improved the outcome of IPIT.

Animals↗
PubMed2006

Adult onset tethered cord syndrome associated with intradural dermoid cyst. A case report.

STUDY DESIGN: A case report and a review of literature. OBJECTIVES: To describe a rare case of adult onset tethered cord syndrome associated with intradural dermoid cyst. SETTING: General Orthopedics, Japan. METHODS: A 50-year-old woman was referred to us because of right leg pain and pollakiuria. Neurological examinations and radiological assessments including myelography, computerized tomography scan and Magnetic resonance image were carried out. We diagnosed it as the adult onset tethered cord syndrome associated with an intradural cystic lesion. RESULTS: The cystic lesion was totally removed following laminectomy from L5 through S4. Histologically, the tumor was diagnosed as a dermoid cyst. CONCLUSIONS: Intradural dermoid could produce adult onset tethered cord syndrome, but it was not reported in the English literatures to our knowledge.

Cauda Equina↗
PubMed2006

Extruded lumbar osseous endplate causing long-term radiculopathy in an adult: an endoscopic excision.

In this report, we described an adult case that had a long-term radiculopathy due to an extruded osseous endplate of the lumbar spine at the L5-S1 intervertebral disc level. The osseous material inside the extruded material was not absorbed, and it had continued compressing the nerve root for one year. Endoscopically, the bony fragment was successfully removed. After the surgery, the patient's symptom disappeared, and neurological deficits became normalized. In conclusion, we propose that surgical intervention should be taken into account for the treatment of HNP, when the extruded material contains bony fragment such as osseous endplate.

Adult↗
PubMed2006

MRI findings of haematomyelia in a dog with spontaneous systemic haemorrhage.

A 7-year-old female cross-breed dog was brought to Nihon University Animal Medical Center for investigation of tetraplegia. Lameness in the pelvic limbs, that had developed 2 weeks previously, had progressed to tetraplegia. On magnetic resonance imaging of the spinal cord, isointensity was detected from C2 to C4 and T12 to T13, isointensity and hyperintensity were intermingled from L3 to L4, and hyperintensity was detected from L5 to L7 by T1-weighted imaging. On T2-weighted imaging, hyperintensity was detected in all regions described above. The dog recovered from anaesthesia, but died during the day from systemic bleeding as the result of a coagulopathy of unknown aetiology. Histopathological examination revealed haematomyelia in these regions of the spinal cord. This is the first report of magnetic resonance imaging findings of haematomyelia in canine spontaneous systemic haemorrhage. It appeared that the differences in the findings of T1-weighted imaging along the spinal regions reflected time-lags in the occurrence of bleeding.

Animals↗
PubMed2006

Demonstration of inter- and intracellular distribution of boron and gadolinium using micro-proton-induced X-ray emission (Micro-PIXE).

Micro-proton-induced X-ray emission (Micro-PIXE) was applied to determine inter- and intracellular distribution of boron (10B) and gadolinium (157Gd), the capture atoms used to kill tumor cells in neutron capture therapy (NCT). Cultured 9L gliosarcoma cells on Mylar film were exposed to sodium borocaptate (BSH) and gadobenate dimeglumine (Gd-BOPTA). To analyze the inter- and intracellular distribution of 10B and 157Gd in 9L gliosarcoma cells, the cells were irradiated using a proton beam of 1.7 or 3 MeV energy collimated to 1 microm diameter and emission X-ray was detected. The distribution of 10B and 157Gd in 9L gliosarcoma cells was then examined. In this study, we could directly analyze the inter- and intracellular distribution of 10B and 157Gd elements in 9L gliosarcoma cells directly using Micro-PIXE. This is the first report on the distribution of 10B employing a method to detect gamma-rays resulting from the nuclear reaction of 10B using particle-induced gamma-ray emission (PIGE). These results show that the distribution of 157Gd elements was correctly measured using micro-PIXE. 157Gd should have the same tendency as 10B in cultured 9L gliosarcoma cells and agree with the distribution in 9L gliosarcoma cells. Further investigation is necessary for a higher spatial resolution and optimization of the measurement time or improvement of the sampling method. In the future, it will be possible to employ this method to analyze the intracellular microdistribution of the capture element and in the development of new drugs for NCT.

Boron↗
PubMed2006

Genetic and phylogenetic characterization of rabies virus isolates from wildlife and livestock in Paraiba, Brazil.

Thirty-four rabies virus (RV) isolates from foxes (8), insectivore bats (9), cattle (14), sheep (1), a goat (1) and a donkey (1) from Paraiba state, northeastern Brazil, were genetically characterized. Sequences of 890 nts of nucleoprotein (N) genes of these isolates were analyzed and compared with those of other Brazilian isolates characterized earlier. Phylogenetic analysis revealed three genetical lineages of RV co-existing in this region. Each lineage was found to be associated with particular host species and to circulate independently of each other. The first lineage was found in foxes (Dusicyon sp.) and could be discriminated from domestic carnivore isolates from Sao Paulo, Goias and Minas Gerais in the southern and central Brazil. The second lineage was associated with insectivorous bats (Molossus spp.) and differed from vampire bat-associated RV isolates. The third lineage was found in livestock and clustered with vampire bat-associated RV isolates from Sao Paulo, Tocantins, Goias and Matto Grosso. These results indicate that RV of these genetic lineages are cocirculating in the Paraiba state and that livestock in this region are infected with vampire bat-associated RV, suggesting that the vampire bat is the main reservoir of livestock rabies in this region.

Animals↗
PubMed2006

[Mediastinal emphysema after a punch on the back; report of a case].

A 19-year-old man was punched on the back, and anterior chest pain appeared about 3 hours after injury. The patient was consulted a physician complaining of anterior chest pain. On chest X-ray, mediastinal emphysema was suspected, and transferred to our hospital. Chest computed tomography (CT) revealed mediastinal emphysema. On esophageal radiography and bronchofiberscopy, no abnormal findings were detected. Conservative therapy was conducted, and symptoms had gradually improved. On the 8th hospital day, mediastinal emphysema was improved on chest CT. The patient was discharged on the 10th hospital day. The most frequent cause of mediastinal emphysema after trauma is traffic or downfall accident, and no report on this condition after the punch on the back was found.

Adult↗
PubMed2006

Spheric mass beneath the alar base: MR images of nasolabial cyst and schwannoma.

We report 2 cases of nasolabial cyst and a case of schwannoma beneath the alar base that required a differential diagnosis because of clinical features and MR images that resembled the nasolabial cyst. The morphologic analysis on MR images revealed the characteristic appearance of the nasolabial cyst, and the sagittal MR image may be most helpful for diagnosing this rare disease.

Adolescent↗
PubMed2005

Biomechanical comparison of lumbar spine with or without spina bifida occulta. A finite element analysis.

STUDY DESIGN: Biomechanical study using finite element model (FEM) of lumbar spine. OBJECTIVES: Very high coincidence of spina bifida occulta (SBO) has been reported more than in 60% of lumbar spondylolysis. The altered biomechanics due to SBO is one considerable factor for this coincidence. Thus, in this study, the biomechanical changes in the lumbar spine due to the presence of SBO were evaluated. SETTING: United States of America (USA). METHODS: An experimentally validated three-dimensional nonlinear FEM of the intact ligamentous L3-S1 segment was used and modified to simulate two kinds of SBO at L5. One model had SBO with no change in the length of the spinous process and the other had a small dysplastic spinous process. Von Mises stresses at pars interarticularis were analyzed in the six degrees of lumbar motion with 400 N axial compression, which simulates the standing position. The range of motion at L4/5 and L5/S1 were also calculated. RESULTS: It was observed that the stresses in all the models were similar, and there was no change in the highest stress value when compared to the intact model. The range of motion was also similar in all the models. The lumbar kinematics of SBO was thus shown to be similar to the intact model. CONCLUSION: SBO does not alter lumbar biomechanics with respect to stress and range of motion. The high coincidence of spondylolysis in spines with SBO may not be due to the mechanical factors.

Biomechanical Phenomena↗