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Biomedical subjects

T Nakashima

Publications and source records attributed to T Nakashima.

At least 289 records · Page 16Linked to original sources

Effect of hemorrhagic hypotension on blood flow to the basal and upper turns of the cochlea.

The effect of hemorrhagic hypotension on blood flow in the cochlea was studied in guinea pigs. Using two laser Doppler probes, simultaneous measurements were made from the basal and upper turns of the cochlea. Hypotension induced by removal of blood resulted in reduction of cochlear blood flow. Cochlear blood flow, however, did not reduce the same extent as the extent of hypotension and the reduction of blood flow was observed to be more remarkable in the upper turns than in the basal turn.

Animals↗

Symphalangism (two phalanges) in the digits of the Japanese foot.

We report here an investigation into the number of phalanges of the 2nd to 5th toes in a Japanese population. The number of phalanges in each of these toes is normally three, distal, middle and proximal. However, occasionally only two phalanges are observed. In this condition, known as symphalangism, the middle and distal phalanges are fused (synarthrosis of the distal interphalangeal joint). The incidence of symphalangism in the 488 feet was found to be 72.5% in the 5th toe, 11.9% in the 4th toe, 0.8% in the 3rd toe, and 0.0% in the 2nd toe. No left-to-right or sex differences were observed. The reported overall incidence of symphalangism in the 5th toe of the foot in the Japanese population (74.7%) is significantly higher than that in the European population (40.2%). In the present sample, the incidence of symphalangism of the 4th toe (11.9%) was significantly higher than that in Japanese population samples previously studied (4.2%).

Adolescent↗

Inner ear barotrauma: computed tomographic evaluation.

Eight patients with inner ear barotrauma were evaluated by computed tomography. The causes of the inner ear barotrauma were diving in four, flying in an airplane in three, and climbing in one. Regarding the width of the cochlear aqueduct, no significant difference was observed between the affected side (3.28 +/- 0.49 mm) and non-affected side (3.63 +/- 0.79 mm) at the base of the infundibulum. The jugular fossa could not be identified on the affected side in three patients. Some relationship may exist between inner ear barotrauma and poor development of the jugular fossa.

Adult↗

Magnitudes of neurological disorders in a farming town in Kyushu, Japan: frequency of neurological symptoms and signs.

We examined 1,270 elderly residents aged 60 years and over in a cross-sectional study of a standardized clinical examination to determine the frequency of 'abnormal' neurological findings in 27 randomly selected communities in the town of Mifune, Japan. The survey showed one or more neurological symptoms in 89.1%, and one or more signs in 94.4% of the examined elderly. Most of the symptoms and signs increased with age, especially after 70 years, indicating the importance of neurological afflictions in the community health of the elderly.

Age Factors↗

Activation of phosphoinositide-specific phospholipase C by transferrin in porcine cerebral arterial smooth muscle cells.

The effect of transferrin on phosphoinositide metabolism was investigated in smooth muscle cells isolated from the porcine basilar artery. Ferric iron-bound transferrin induced a rapid increase in the level of inositol phosphates, the metabolic products of phosphoinositides through the phospholipase C pathway. Neither transferrin free of ferric iron nor ferric iron alone caused the activation of phospholipase C. This study suggests that ferric iron-bound transferrin is capable of eliciting receptor-mediated signal transduction in porcine cerebral arterial smooth muscle cells, which could result in the contraction of smooth muscle cells. Transferrin may be involved with the cerebral arterial narrowing in pathological conditions such as subarachnoid hemorrhage.

Animals↗

Cytosolic free calcium elevation in vascular smooth muscle cells induced by cerebrospinal fluid from patients with subarachnoid hemorrhage--biochemical nature of the calcium-mobilizing factor.

The present study was undertaken to characterize the biochemical nature of the factor in cerebrospinal fluid (CSF) from patients with subarachnoid hemorrhage (SAH) that induces a transient elevation of cytosolic free calcium in cultured vascular smooth muscle cells. Cell-free CSF collected from patients on days 7-10 after SAH was treated in three different ways: heating, ultrafiltration, and salting out with ammonium sulfate. The effects of the resultant solutions on the level of cytosolic free calcium in cultured vascular smooth muscle cells were then examined. Heated CSF and ultrafiltrated solution containing substances with molecular weights of less than 10,000 caused no significant elevation of cytosolic free calcium. Proteins precipitated by 50-75% saturated ammonium sulfate caused an increase in the level of cytosolic free calcium and also produced a rapid accumulation of inositol 1,4,5-trisphosphate in vascular smooth muscle cells. The results indicate that the factor responsible for the increase in cytosolic free calcium in cultured vascular smooth muscle cells is a protein with a molecular weight of more than 10,000, and the factor stimulates receptor-mediated phosphoinositide breakdown.

Calcium↗

Effect of carbon dioxide on facial nerve blood flow in rabbits.

We investigated blood flow to the facial nerve, cerebral cortex, brain stem, and dura mater in 16 white rabbits using a nonradioactive microsphere technique at various levels of arterial carbon dioxide tension. The blood flow to the facial nerve in the 32 temporal bones was 59.1 +/- 32.9 microliters/g/min. Unlike cerebral blood flow, blood flow to the facial nerve and dura mater did not show any marked increase upon carbon dioxide inhalation.

Administration, Inhalation↗

[Measurement of cochlear blood flow during exploratory tympanotomy in patients suspected of having perilymphatic fistulas].

Since impairment of cochlear blood flow is one of the factors implicated in the pathophysiology of sudden deafness, we measured cochlear blood flow in nine patients suspected of having perilymphatic fistulas. All but one patient had sudden sensorineural hearing loss. The exceptional case had experienced rotatory vertigo immediately after nose-blowing. In the eight patients with sudden deafness, the average hearing level ranged from 30dB to 80dB. Among these patients, there was a first reported case of recurrent inner ear barotrauma due to diving. This case was a 41-year-old male who had a second episode of sudden deafness six years after the first sudden deafness episode affecting the same ear. During exploratory tympanotomy, the tip of a laser-Doppler probe was attached to the promontory near the anterior superior portion of the round window niche. The outer diameter of the probe was 1.7mm and the distance between the exciting and receiving optic fibers was 1.0mm. Pulsatory movement of the laser-Doppler output was observed in all 9 patients even after the middle ear mucosa had been removed. We attempted to measure the effects of carbon dioxide on cochlear blood flow, using methods such as inhalation of carbogen and cessation of respiration. In most cases, however, no significant change in cochlear blood flow was observed with these procedures.

Adult↗

[Continent urinary diversion with the Florida pouch].

From October 1990 through June 1993, the Florida pouch, a continent urinary reservoir using the ascending colon and the dexter half of the transverse colon was constructed in 7 patients after cystectomy for invasive tumor. Concerning the length of the efferent limb, although 10 cm was adopted in the first three cases, we shortened it and finally considered 8 cm to be the adequate length. Although the capacity of the reservoir ranged from 90 ml to 180 ml immediately after operation, an increase of capacity by three times or more within three months after operation was seen. The patients performed self-catheterization 4-5 times during the day and 0-2 times at night for volumes ranging from 300 to 600 ml. Continent colonic urinary diversion did not appear to create either any significant acid-base changes or azotemia in patients with normal renal function. Every patient received both a serum value evaluation and an absorption test for vitamin B12 (Schilling test). Although there were no patients with a reduced serum vitamin B12 level, one patient showed a slightly low absorption value. Because there is a large quantity of vitamin B12 reserve in the liver, it must be emphasized that even when the entero-hepatic circulation has been injured by surgical interruption of the intestinal tract, it may be years before reduced serum vitamin B12 value become apparent. Accordingly, the vitamin B12 absorption test should be performed regardless of the ileal length incorporated into the resection.

Aged↗

[High resolution MR imaging of the inner ear apparatus using 3D-Fast spin echo sequence].

To evaluate the efficacy of high resolution MR imaging of the inner ear with 3D-Fast spin echo sequence, one volunteer and 12 patients were imaged with a 1.5 T MR scanner. High resolution T2-weighted images were obtained with a head coil in 13 minutes, and the voxel size was 0.39mm x 0.45mm x 1.2mm in most subjects. Original images and maximum intensity projection (MIP) images of the inner ear were evaluated. On original images, the endolymphatic duct was visualized in 72% of subjects, the cochlear aqueduct in 96%, three branches of the cranial nerves in the internal auditory canal in 100%, and flow void of the vessel in the cerebellopontine angle in 100%. On MIP images, more than two cochlear turns were visualized in 92% of subjects, three semicircular canals in 100%, and the anterior and posterior ampulla in 100%. MR imaging of the inner ear with 3D-Fast Spin Echo sequence provides a variety of useful information regarding the anatomy around the inner ear.

Ear, Inner↗

Effectiveness of bovine gallstone (Goou) and bear gall powder (Yutan) on chronic liver diseases: a preliminary report.

The author reports 23 cases of chronic liver disease which showed remarkable improvement with the administration of bovine gallstone (Goou) and bear gall powder (Yutan). The concomitant administration of both Goou at 200 mg/day and Yutan at 60 mg/day resulted in marked improvement of liver function as well as subjective complaints in all the patients within one month. The administration of Goou alone was also effective, but concomitant administration of Goou and Yutan tended to be more effective than administration of Goou alone in cases of liver cirrhosis. These results suggest that animal crude drugs (Goou and Yutan) are reliable medicines for intractable chronic liver diseases.

Adult↗

Molecular genotyping for N-acetylation polymorphism in Japanese patients with colorectal cancer.

BACKGROUND: N-acetylation polymorphism has been documented as a representative pharmacogenetic trait, and also has been implicated ecogenetically in an individual's susceptibility to cancer. However, there still remains controversy concerning the association between colorectal cancer and N-acetylation polymorphism. METHODS: A newly established molecular genotyping method using polymerase chain reaction-based restriction fragment length polymorphism to analyze the distribution of polymorphism in a large group of Japanese patients with colorectal cancer was used. RESULTS: Based on an analysis of 234 Japanese patient with colorectal cancer and 329 healthy control subjects, no significant difference was observed in either the distribution of acetylator phenotypes or of allele frequencies between the two groups. In addition, no significant difference in their distribution was found based on the age at which cancer was first detected, the location of tumors, or the histopathologic features. CONCLUSIONS: N-acetylation polymorphism does not appear to be implicated crucially as a genetic trait affecting an individual's susceptibility to colorectal cancer.

Acetylation↗

Multiple occurrence of carcinoma in the upper aerodigestive tract associated with esophageal cancer: reference to smoking, drinking and family history.

Smoking and drinking habits as well as family history were examined in 143 men with esophageal cancer, including 30 who had associated second cancers of the upper aerodigestive tract (UADT) and 113 who did not. The risk of second cancers of UADT associated with the main lesions of the esophagus was evaluated, using odds ratios (ORs). As a result, the ORs of second cancers for current smoking and drinking were 5.3 and 7.6 respectively. The ORs significantly increased to 12.7 and 14.7 in heavy smokers and in heavy drinkers respectively. Furthermore, the risk of second cancer also significantly increased (8-fold) in patients who had close relatives with UADT cancer, compared to those without family history of any cancer. However, there were no differences in smoking or drinking habits regardless of family history. Our data thus suggest that a family history of UADT cancer as well as heavy smoking and drinking are clearly associated with multiple occurrence of UADT cancer. Therefore, careful and frequent examination for appearance of any second lesions are required for patients in these high-risk groups.

Aged↗

Expression of c-fos immunoreactivity in the hypothalamic magnocellular neurons during chronic osmotic stimulations.

The immunoreactivity of c-fos protein was transiently detected in magnocellular neurons of the supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the rat hypothalamus after intraperitoneal injection of hypertonic NaCl solution. In contrast, c-fos-positive magnocellular neurons were persistently observed in the SON and PVN of the rats which were chronically stimulated by the drinking of hypertonic NaCl solution instead of water or by water deprivation. c-fos immunoreactivity was eliminated in the animals which were allowed to drink tap water for 24 h following the chronic osmotic stimulations. These results suggest that persistent expression of c-fos protein is closely associated with the neural plasticity of the hypothalamic magnocellular neuron.

Administration, Oral↗

Structure of the human CCG1 gene: relationship between the exons/introns and functional domain/modules of the protein.

The human CCG1 gene, encoding CCG1/TAFII250/p250, was isolated by complementing tsBN462, a mutant BHK21 cell line that shows cell-cycle arrest at high temperature. Using the cDNA as a probe, the locations of exon-intron junctions were determined in the genomic DNA. Thirty-eight exons ranging from 68 to 219 bp in size were found. All the exon-intron junctions followed the GT-AG rule. Using a newly developed method, we performed a module analysis of the CCG1 protein. The functional domain previously predicted in CCG1 was further confirmed to be encoded in a single predicted module that is the minimal functional unit in the protein. The boundaries of the predicted modules show a close correlation to the intron/exon junction of CCG1. The entire gene, at least 110 kb long, has been recovered in a YAC, which provides a route to the further study of module function.

Base Sequence↗