Biomedical subjects

Yorito Anamizu

Publications and source records attributed to Yorito Anamizu.

5 recordsLinked to original sources

PubMed2006

Age-related changes in histogram pattern of anterior horn cells in human cervical spinal cord.

The purpose of the present study was to clarify age-related changes in histograms of spinal anterior horn cells. The study examined Rexed lamina IX of the C7 spinal cord segment in 22 men who had died of non-spinal disease (age range, 0-85 years). First, we confirmed that the size of nucleoli exhibited a linear relationship to the diameter of spinal anterior horn cells by preparing histograms of nucleoli. Second, this formula was used to create histograms of cervical anterior horn cells. Results were as follows: (i) diameter of nucleoli ranged from 2.0 microm to 6.0 microm; (ii) in each subject, no changes were seen in histogram patterns among ventral, intermediate, dorsal and overall sections; (iii) at < or =20 years of age, histograms displayed a single peak for the diameter of nucleoli at about 4.0-4.5 microm; (iv) at 21-60 years of age, histograms displayed two peaks, at about 3.5-4.0 microm and 5.0-5.5 microm; and (v) at 61-85 years of age, histograms displayed a single peak at about 5.0-5.5 microm.

Adolescent↗

PubMed2005

Ossification of the posterior atlantoaxial membrane and the transverse atlantal ligament.

STUDY DESIGN: Case report. OBJECTIVE: To report a case of ossification of the posterior atlantoaxial membrane (PAAM) and ossification of the transverse ligament of the atlas (TAL). SUMMARY OF BACKGROUND DATA: Ossification of the PAAM and TAL are both very rare clinical entities. This is the first case involving ossification of both the PAAM and TAL with the development of cervical myelopathy. METHODS: Patient's history, physical examination, radiographic evaluation, surgical treatment, and outcome are examined. Relevant literature is also reviewed. RESULTS: The patient's neurological symptoms significantly improved after posterior decompressive surgery. CONCLUSION: Ossification of various parts of the spinal ligament have been reported previously. Among them, ossification of both the PAAM and TAL has never been reported previously and is thus extremely rare. Surgical intervention improved the neurological impairment.

Aged↗

PubMed2005

Klotho insufficiency causes decrease of ribosomal RNA gene transcription activity, cytoplasmic RNA and rough ER in the spinal anterior horn cells.

The klotho gene was identified in 1997 as the gene whose severe insufficiency (kl/kl) causes a syndrome resembling human aging, such as osteoporosis, arteriosclerosis, gonadal atrophy, emphysema, and short life span in a mouse strain. Regarding the gait disturbance reported in kl/kl mice, the present study examined the spinal cord of kl/kl mice, and revealed decreases in the number of large anterior horn cells (AHCs), the amount of cytoplasmic RNA, the number of ribosomes and rough endoplasmic reticulum (rER), and the activity of ribosomal (r) RNA gene transcription without significant loss of the total number of neurons in the ventral gray matter. Increased immunostaining of phosphorylated neurofilament in the AHCs and of glial fibrillary acidic protein in reactive astrocytes in the anterior horn of kl/kl mice were also observed. On the other hand, the posterior horn was quite well preserved. The results suggest that the kl/kl insufficiency causes atrophy and dysfunction of the spinal AHCs through decreased activity of rRNA gene transcription, which may reduce the amount of cytoplasmic RNA and the number of ribosomes and rER. These findings resemble those found in the spinal cord of patients with classic amyotrophic lateral sclerosis (ALS). The results show that klotho gene insufficiency causes dysfunction of the protein synthesizing system in the AHCs, and might indicate the klotho gene is involved in the pathological mechanism of classic ALS. The kl/kl is a new animal model of AHC degeneration, and may provide clues to understanding the etiology of classic ALS.

Animals↗

PubMed2004

Measurement of occipitocervical angle.

STUDY DESIGN: This study compared the reliability of 3 techniques used to measure alignment between the occiput and cervical spine. OBJECTIVES: Intraobserver and interobserver intraclass correlation coefficient were computed to determine the most reliable method to measure occipitocervical angle. SUMMARY OF BACKGROUND DATA: No studies have been performed comparing occipitocervical angle measurement techniques. METHODS: The angles between the inferior endplate of second cervical vertebrae and the occiput line using the Chamberlain line, McRae line, and McGregor line were measured from lateral cervical radiographs of 30 healthy volunteers. Five spine surgeons made measurements. RESULTS: Mean intraobserver variances of the angles using Chamberlain line, McRae line, and McGregor line were 2.0 degrees (ranging from 0 degrees-15 degrees), 4.7 degrees (from 0 degrees-28 degrees), and 1.5 degrees (from 0 degrees-9 degrees), respectively; intraobserver intraclass correlation coefficients of the angles were 0.956, 0.835, and 0.975. Mean interobserver variances of the angles using Chamberlain line, McRae line, and McGregor line were 2.3 degrees (from 0.4 degrees-6.4 degrees), 5.0 degrees (from 1.8 degrees-11.9 degrees), and 1.4 degrees (from 0 degrees-4.5 degrees), respectively; interobserver intraclass correlation coefficients were 0.939, 0.802, and 0.972. The highest reliability indexes were obtained for McGregor line. CONCLUSIONS: The McGregor line is the most reproducible and reliable method for measurement of the occipitocervical angle.

Anthropometry↗

PubMed2004

Case of idiopathic thoracic spinal cord herniation with a chronic history: a case report and review of the literature.

Idiopathic spinal cord herniation is a rare disease that presents with slowly progressive myelopathy. This article describes the clinical findings of a patient with a chronic history. A 68-year-old woman initially presented at the age of 32 years with left leg weakness. After slowly progressive neurological deterioration over 34 years, she became completely paraplegic. At the age of 66 years, magnetic resonance imaging resulted in a diagnosis of idiopathic spinal cord herniation at the T6/7 level. Surgery was performed to reduce aching of the lower extremities. The spinal cord was released from the dural defect through a T5-T8 laminectomy. The dural defect was enlarged by resecting its periphery to prevent reherniation of the spinal cord. After the surgery, pain in the lower extremities resolved and her motor function slightly improved. Although operative treatment is naturally recommended at the early stage of this disease, our case suggests that some symptoms can be resolved by surgical treatment despite prolonged, severe preoperative symptoms.

Aged↗