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Isao Nakamura

Publications and source records attributed to Isao Nakamura.

17 recordsLinked to original sources
PubMed2006

Computer-assisted screw insertion for cervical disorders in rheumatoid arthritis.

To reconstruct highly destructed unstable rheumatoid arthritis (RA) cervical lesions, the authors have been using C1/2 transarticular and cervical pedicle screw fixations. Pedicle screw fixation and C1/2 transarticular screw fixation are biomechanically superior to other fixation techniques for RA patients. However, due to severe spinal deformity and small anatomical size of the vertebra, including the lateral mass and pedicle, in the most RA cervical lesions, these screw fixation procedures are technically demanding and pose the potential risk of neurovascular injuries. The purpose of this study was to evaluate the accuracy and safety of cervical pedicle screw insertion to the deformed, fragile, and small RA spine lesions using computer-assisted image-guidance systems. A frameless, stereotactic image-guidance system that is CT-based, and optoelectronic was used for correct screw placement. A total of 21 patients (16 females, 5 males) with cervical disorders due to RA were surgically treated using the image-guidance system. Postoperative computerized tomography and plane X-ray was used to determine the accuracy of the screw placement. Neural and vascular complications associated with screw insertion and postoperative neural recovery were evaluated. Postoperative radiological evaluations revealed that only 1 (2.1%; C4) of 48 screws inserted into the cervical pedicle had perforated the vertebral artery canal more than 25% (critical breach). However, no neurovascular complications were observed. According to Ranawat's classification, 9 patients remained the same, and 12 patients showed improvement. Instrumentation failure, loss of reduction, or nonunion was not observed at the final follow-up (average 49.5 months; range 24-96 months). In this study, the authors demonstrated that image-guidance systems could be applied safely to the cervical lesions caused by RA. Image-guidance systems are useful tools in preoperative planning and in transarticular or transpedicular screw placement in the cervical spine of RA patients.

Aged↗
PubMed2006

Posterior correction and fusion for severe cervical kyphosis in a patient with myotonic dystrophy: a case report.

STUDY DESIGN: A case report. OBJECTIVE: To report the first myotonic dystrophy case in which cervical kyphosis had been surgically corrected. SUMMARY OF BACKGROUND DATA: Myotonic dystrophy is an autosomal dominant disease that shows myotonia, progressive muscle atrophy, and other various symptoms. Instability of the neck is expected to cause disorders of the cervical spine; however, there are no detailed reports on deformity of cervical spine associated with this disease. METHODS: A 43-year-old man with cervical kyphosis due to myotonic dystrophy had undergone an occiput-T2 fusion with autogenous iliac bone using spinal instrumentation. RESULTS: The activity of daily life of the patient had improved markedly, and the good results continued to be preserved for 5 years. There were not any major perioperative complications. CONCLUSIONS: Surgical correction of cervical spine is not necessarily a contraindication for myotonic dystrophy.

Adult↗
PubMed2005

Adsorption and reactions of NO on clean and CO-precovered Ir(111).

Adsorption and reactions of NO on clean and CO-precovered Ir(111) were investigated by means of X-ray photoelectron spectroscopy (XPS), high-resolution electron energy loss spectroscopy (HR-EELS), infrared reflection absorption spectroscopy (IRAS), and temperature-programmed desorption (TPD). Two NO adsorption states, indicative of fcc-hollow sites and atop sites, were present on the Ir(111) surface at saturation coverage. NO adsorbed on hollow sites dissociated to Na and Oa at temperatures above 283 K. The dissociated Na desorbed to form N2 by recombination of Na at 574 K and by a disproportionation reaction between atop-NO and Na at 471 K. Preadsorbed CO inhibited the adsorption of NO on atop sites, whereas adsorption on hollow sites was not affected by the coexistence of CO. The adsorbed CO reacted with dissociated Oa and desorbed as CO2 at 574 K.

Journal Article↗
PubMed2005

Studies of NO adsorption on Pt(110)-(1 x 2) and (1 x 1) surfaces using density functional theory.

Adsorption of NO on Pt(110)-(1 x 2) and (1 x 1) surfaces has been investigated by density functional theory (DFT) method (periodic DMol(3)) with full geometry optimization and without symmetry restriction. Adsorption energies, structures, and N-O stretching vibrational frequencies of NO are studied by considering multiple possible adsorption sites and comparing with the experimental data. Adsorption is strongly dependent on both coverage and surface phase. The assignment of adsorption sites has been carried out with precise calculation of vibrational frequencies for NO on various sites. We clearly show the NO site switching on both of the surfaces as found in the experiments: at low coverages, bridge species is formed on the surface, and at high coverages, NO switches to atop sites.

Journal Article↗
PubMed2005

A density functional study of NO adsorption and decomposition on Ni(211) and Pd(211) surfaces.

The adsorption and decomposition of NO have been investigated by using density functional theory method at the generalized gradient approximation level. We have performed calculations on adsorption energies and structures of NO on Ni(211) and Pd(211) surfaces with full-geometry optimization and compared them with the experimental data. The most favorite adsorption on both surfaces occurs at the bridge site parallel to step edge (sb), while the energy difference from the second favorite site of a threefold hollow site near step edge is less than 0.1 eV. Decomposition pathways have been investigated with transition state search. The decomposition pathway, where NO leans toward the step, is most probable for both surfaces. The overall activation energy for decomposition is 0.39 and 1.26 eV for Ni(211) and Pd(211), respectively. The present results clearly show that the NO molecules on Pd(211) are less activated than those on Ni(211). We have studied also reorganization of NO on Pd(211) at higher coverages up to 1/3 ML (monolayer) [three NO molecules in a (3 x 1) unit cell]. The site occupation is not in a sequential manner as the NO coverage is increased, and a reorganization of NO adsorbates occurs (the NO molecule at sb becomes tilting up at higher coverage), which can interpret the experimental data of Yates and co-workers very well.

Journal Article↗
PubMed2005

Usefulness of post-mortem ophthalmological endoscopy during forensic autopsy: a case report.

Post-mortem intraocular findings in two autopsy cases with traumatic intracranial haemorrhage were obtained using an ophthalmological endoscope. The endoscopy results clearly revealed the presence of intraocular haemorrhages and papilledema caused by intracranial haemorrhage. Post-mortem ophthalmological endoscopy offers several benefits. First, post-mortem intraocular findings can be directly observed in corpses with post-mortem clouding of the cornea. Secondly, the endoscopy only requires a 0.9 mm incision in the sclera and does not require the removal of the eye from the corpse, a procedure that should be avoided for ethical and cosmetic reasons. Thus, post-mortem opthalmological endoscopy is a useful method for obtaining intraocular findings in autopsies.

Aged↗
PubMed2004

[Vertebroplasty].

Vertebroplasty for pseudoartrosis of vertebral fracture using PMMA (polymethylmetacrylate) or CPC (calcium phosphate cement) is a new less invasive surgical method providing sufficient pain relief and correction of kyphosis.

Calcium Phosphates↗
PubMed2003

Clinical outcome and survival after palliative surgery for spinal metastases: palliative surgery in spinal metastases.

BACKGROUND: The authors sought to identify treatment-related factors that influenced survival after surgical treatment for metastatic spinal tumors and to evaluate the relationship between survival and postoperative ambulation time as a factor related to quality of life. METHODS: The medical records of 81 patients with metastatic spinal tumors who underwent palliative surgery at the study institution were assessed. Univariate analysis for factors influencing survival used the Kaplan-Meier log rank statistic and multivariate analysis used the Cox proportional hazards model. The Spearman correlation test was used to analyze the relationship between postoperative ambulation and survival time. RESULTS: The patients had a median age of 59.9 years and a median survival of 10.6 months after surgery. For patients, postoperative ambulatory median survival was 16.5 months and median ambulation time was 13.8 months. By univariate analysis, anatomic site of the primary tumor, postoperative ambulation, and combined adjuvant therapy (chemotherapy plus radiotherapy) were associated with prolonged survival (P < 0.05). Multivariate analysis identified primary site and postoperative ambulatory function as independent predictors of prolonged survival (P < 0.0001). Significant correlations were found between ambulation time and survival time of patients who were able to walk after surgery (P < 0.0001), even in patients with liver (P < 0.05) or lung carcinoma (P < 0.05). CONCLUSIONS: The anatomic site of primary carcinoma and postoperative ambulation were associated with longer survival after palliative surgery for metastatic spinal tumor. When ambulation is attained after surgery, it can be preserved until late in remaining life even when the primary tumor is unfavorable. Palliative surgery for spinal metastasis can improve the quality and quantity of life.

Early Ambulation↗
PubMed2003

Elder abuse and neglect: social problems revealed from 15 autopsy cases.

This study examined the elder abuse cases that occurred in Gifu Prefecture, Japan between 1990 and 2000. We conducted a retrospective study of all the cases in which the victim was 65 years or older and autopsied in the Department of Legal Medicine, Gifu University School of Medicine. Fifteen victims were classified as elder abuse victims: five men and ten women. The victims ranged in age from 66 to 87 years (mean age, 74.5 years). The types of abuse were as follows: physical abuse, 13 cases; emotional abuse, five cases; neglect, four cases; and financial abuse, three cases. In eight cases, the victims were subjected to two or more types of abuse. The cause of death of the victims varied with the type of abuse. In the physical abuse cases, subdural hemorrhage was the most common cause, followed by other violence-related deaths and hypothermia. In the neglect cases, the victims died of either starvation or suffocation after the aspiration of food into the airway. In the domestic abuse cases, one of the victim's sons was the most common perpetrator, and little or no income was considered to be a risk factor for perpetrators. In the neglect cases, dementia and difficulty in performing activities of daily living were considered to be risk factors for victims, in addition to living in social isolation.

Aged↗
PubMed2003

DNA typing from cigarette butts.

We performed DNA typing for D1S80, HLADQA1, TH01 and PM using the butts of 100 cigarettes that were smoked by ten different individuals (ten cigarettes per individual). The results obtained from DNA typing for D1S80 agreed with the results obtained using bloodstains in 76 cigarette butt samples. Sixteen samples produced false results, showing the loss of the longer allelic hetero-band. When examined using agarose gel electrophoresis, high-molecular weight DNA was not observed in these samples. The same results were also observed for buccal swab samples and saliva stains obtained from the same individuals. In the remaining eight cigarette butt samples, PCR products were not detected. The results obtained from DNA typing for TH01, HLADQA1 and PM agreed with the results obtained using bloodstains in 90 samples. In the remaining ten samples of a specific kind of cigarette (Marlboro), the PCR products were not detected. The extracts from the ends of the Marlboro cigarettes were stained yellow. When the DNA extracted from Marlboro cigarette butts was treated with Microcon-100 (amicon) or SizeSep 400 Span Columns (Amersham Pharmacia Biotech), PCR products could be detected. When PCR amplification was performed after adding extracts from the ends of unsmoked Marlboro cigarettes to DNA extracted from bloodstains, PCR products could not be detected. The present data indicate that the degradation of high-molecular weight DNA and the inhibition of PCR by dyes of the cigarette end should be kept in mind when performing DNA typing using cigarette ends.

Adult↗
PubMed2003

Quality and quantity of DNA in cadavers' serum.

We investigated the quality and quantity of DNA in sera obtained from 16 cadavers who were left at room temperature or placed in a refrigerator for cadavers within 3 days of their death. The causes of death were as follows: asphyxia, 4; hemorrhage, 4; fire, 3; cold, 1; subdural bleeding, 1; sepsis, 1; cerebral contusion, 1; and pulmonary thromboembolism, 1. When examined using agarose gel electrophoresis, the samples from the victims who died from sepsis and pulmonary thromboembolism exhibited smear patterns, while the other samples exhibited ladder patterns. The size of each band was an integer multiple of approximately 180 bp, considered to be characteristic of apoptosis. The DNA concentration in the cadavers' sera ranged from 3.0 to 258.9 ng/ml. DNA types (D1S80, HLADQA1, TH01, and PM) were determined for all the samples except for the sample from the victim who died from sepsis. The detected types were the same as those obtained from paired bloodstain samples, except for in the asphyxia victim. D1S80 typing of the serum sample from the asphyxia victim showed the loss of the longer allelic hetero-band. These results suggest that the quantity of DNA in serum from cadavers is sufficient for DNA typing, but that the degradation of DNA may proceed quickly, depending on the temperature of the area in which the cadaver is left as well as the pathological conditions that the victim had experienced.

Adolescent↗
PubMed2003

Sequence polymorphism of mitochondrial DNA in Japanese individuals from Gifu Prefecture.

Sequence polymorphisms of the hypervariable region HV1 in mitochondrial DNA (mtDNA) were analyzed in a sample of 137 unrelated Japanese individuals living in Gifu Prefecture (central region of Japan) using polymerase chain reaction amplification and direct sequencing. Eighty-two different haplotypes resulting from 81 variable sites were found in the mtDNA HV1 region between positions 16061 and 16450. The most frequent haplotype (16223T, 16362C) was shared by ten individuals. The genetic diversity and the genetic identity were 0.985 and 0.022, respectively. The C-stretch region located around position 16189 was observed in 23.4% of this population sample. Sequence heteroplasmy at the position 16103 (A/G) was found in one individual.

DNA Fingerprinting↗
PubMed2003

Usefulness of postmortem ocular findings in forensic autopsy.

We report three autopsy cases in which the eyeballs were removed and examined macroscopically and microscopically after being cut using the alternate gross examination technique. The first case was a 67-year-old woman who was killed by ligature and manual strangulation. A postmortem opthalmological observation of the left eyeball revealed tiny hemorrhages and congestion in the pars plicae of the ciliary body. These changes were considered to arise by a mechanism similar to that by which facial hemorrhages arise during strangulation. The second case was a 54-year-old man who died from a cerebral contusion received during a traffic accident. A postmortem opthalmological observation of the eyeball using a surgical microscope revealed papilledema and retinal hemorrhages resulting from a rise in intracranial pressure. The third case was a 77-year-old woman who died from cardiac tamponade caused by a stab wound to the heart. A postmortem ophthalmological examination revealed that she had undergone cataract surgery and an intraocular lens implantation. However, her relatives did not know when and where she had received the surgery. An intraocular lens was removed and its material and shape was examined. Based on an examination of the lens, we were able to locate the hospital where she had received the surgery 4 years earlier. This suggests that postmortem opthalmological observations may be useful for forensic pathology and personal identification.

Aged↗
PubMed2003

Myocardial damage by resuscitation methods.

Medico-legal autopsy cases were reviewed to detect myocardial changes induced by resuscitation methods. Myofibrillar degeneration (MFD) induced by resuscitation methods was classified into two types according to Luxol fast blue staining: contraction band (CB) and diffuse staining (DS). In the cases in which cardiopulmonary resuscitation had been performed, myocytes showing CB or DS formed small foci and were distributed in the papillary muscles, septum, and inner to middle layers of the myocardium. MFD induced by vasopressors was characterized by solitary distribution of degenerating myocytes that mainly showed DS and sometimes CB. When direct current countershocks had been performed, focal MFD in the subepicardial zone appeared to be a characteristic feature.

Cardiopulmonary Resuscitation↗
PubMed2002

Preoperative CT examination for accurate and safe anterior spinal instrumentation surgery with endoscopic approach.

The purpose of this article is to introduce a new procedure for the surgical planning of thoracic anterior spinal instrumentation via endoscopy. For accurate and safe anterior screw insertion via the endoscopic approach, we devised a surgical plan based on the preoperative chest computed tomography (CT) findings obtained with radiographic markers. Using this method, we performed endoscopic thoracic spinal instrumentation surgery in 14 patients. Nine patients underwent anterior endoscopic correction and fusion of idiopathic scoliosis by Cotrel-Dubousset instrumentation, and five patients underwent anterior endoscopic spinal fixation with instrumentation. The accuracy of screw insertion was evaluated postoperatively by CT scanning. One interbody fusion cage and 53 screws were inserted in the 14 patients using endoscopy. Postoperative CT scans revealed that the screws were all accurately inserted without any neurologic complications. In conclusion, using this novel procedure for surgical planning based on CT findings obtained with radiographic markers, anterior screws can be inserted safely and accurately via an endoscopic approach.

Adolescent↗
PubMed2002

[Introduction of the electronic anesthesia record keeping system].

Based on five-year experience, we have evaluated the electronic anesthesia record keeping system (DS 5300 OR, Fukuda Denshi, Tokyo), which is the first commercially available system combined with an anesthesia monitor in Japan. Although keying in of text with a keyboard on the screen remains to be improved, the user interface of touch screens is easy to use. It seems to be a great advantage that physiologic variables are automatically and accurately captured very minute. The record is more complete, legible, and accurate than a hand-written record. Both long-term storage and search for the data are much easier. The investment in this system is affordable even for small hospitals. Although there might be some areas in which improvement is needed, we are satisfied with its usefulness and reliability.

Anesthesia↗