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Biomedical subjects

A Tsunoda

Publications and source records attributed to A Tsunoda.

At least 37 records · Page 2Linked to original sources
PubMed2000

Sensorineural hearing loss caused by a high jugular bulb.

A 15-year-old female presented with sensorineural hearing loss related to a high jugular bulb. She noticed temporary worsening of her right hearing with mild dizziness when her neck was compressed whereas she noticed no change in her left hearing. An audiogram showed temporary worsening of low tone bone-conduction on such occasions. A large jugular bulb covering the right round window was observed through the perforation. Computed tomography (CT) revealed a large jugular bulb obliterating the round window niche. Deterioration of bone conduction during neck compression was thought to be caused by the protrusion of the jugular bulb into the inner ear via the round window. This case suggested the possibility of sensorineural hearing loss due to the jugular bulb. As in the present case, jugular bulb or vein-related ear disorders should be examined by neck compression.

Adolescent↗
PubMed2000

The arcuate eminence is not a protrusion of the superior semi-circular canal but a trace of sulcus on the temporal lobe.

Thirteen cadavers (26 temporal bones) were examined to show the arcuate eminence, especially its correspondence to the superior semicircular canal and inferior surface of the temporal lobe. Arc-like eminences on the petrous bone were observed in 92 per cent of specimens, however, they did not exactly correspond to the superior semi-circular canal. Some eminences corresponded to sulci of the temporal lobe of which most were traces of the occipitotemporal sulcus. On the other hand, a dull, smooth and even domed eminence existed in nine temporal bones independently of the arc-like eminence. Those eminences corresponded to each superior semi-circular canal in only three out of nine specimens. The arcuate eminence was listed as an important landmark in the middle cranial fossa approach. However, in order to drill out the internal auditory canal safety, surgeons should rely on other landmarks or apply other methods from our data.

Humans↗
PubMed2000

Prediction of the nerves of origin of vestibular schwannomas with vestibular evoked myogenic potentials.

OBJECTIVE: To determine whether the nerves of origin of vestibular schwannomas can be predicted using vestibular evoked myogenic potentials (VEMPs). STUDY DESIGN: The study was a retrospective analysis. SETTING: The ear, nose, and throat department of Tokyo Medical and Dental University. PATIENTS: Twenty-eight patients undergoing removal of vestibular schwannomas were included in the study. INTERVENTIONS: Patients underwent pure tone audiometry, VEMP testing, caloric testing, and magnetic resonance imaging preoperatively. Hearing level, caloric weakness, maximum tumor size, and the nerves of origin of tumors were compared with VEMP testing. MAIN OUTCOME MEASURE: Results of VEMP testing. RESULTS: Comparisons between VEMPs and results of the other three examinations revealed no correlations. Complete disappearance of VEMPs was observed only in patients with tumors arising from inferior vestibular nerves. Patients in whom hearing was preserved tended to have preserved VEMPs. Some patients showed damaged hearing and normal VEMP results, although with inferior vestibular schwannomas. A patient with a tumor arising from a cochlear nerve exhibited preservation of VEMP, preserved caloric response, and moderate hearing loss. CONCLUSIONS: Inferior vestibular nerve function and hearing level were reflected in VEMP results. Prediction of the nerve of origin of a tumor was possible only in certain restricted cases.

Adult↗
PubMed2000

[Primary pineal embryonal carcinoma occurring in a middle aged man].

A case of a primary pineal embryonal carcinoma occurring in a middle aged man is reported. A 42-year-old man suffering from headache and nausea was referred to our department. A neurological examination revealed that he had Parinaud's sign. Head CT and MRI showed a tumor in the pineal region. He was operated on using the occipital trans-tentorial approach. The tumor was partially removed and an intra-operative specimen was used to diagnose a kind of germ cell line tumor. However, the tumor was diagnosed afterwards as a pure embryonal carcinoma. Three courses of PE chemotherapy followed by 30 Gy of whole craniospinal irradiation and 30 Gy of extended local irradiation were completed. An MRI showed the tumor to be in complete remission. Despite careful follow-up with chemotherapy every three months, a re-operation and linac radio-surgery, the tumor recurred, and disseminated. The patient died due to an intra-tumoral hemorrhage. A pure primary pineal embryonal carcinoma occurring in a middle-aged person has never been reported previously in detail.

Adult↗
PubMed1999

Anorectal function after anterior resection with side-to-side anastomosis for carcinoma of the rectum.

PURPOSE: The aim of this study is to demonstrate whether anorectal function after anterior resection with side-to-side anastomosis results in better clinical outcomes than end-to-end anastomosis in patients with carcinoma of the upper half of the rectum. METHODS: Anorectal function was studied in two groups of patients who had anterior resection, those with end-to-end anastomosis (Group E; n = 11) and those with side-to-side anastomosis (Group S; n = 11). Eight control subjects who had sigmoid colectomy for carcinoma were also studied. Each patient underwent manometric study and was questioned about clinical bowel symptoms before the operation and 3, 6, and 12 months postoperatively. RESULTS: The median length of residual rectum in both Group S and Group E was 7 cm. No significant difference was observed in maximum anal resting pressure and maximum squeeze pressure between the groups before and after operation. Maximum tolerable volume in Group S was significantly higher than that in Group E and was close to that in the control group at each postoperative interval. Median volumes in Group S were 200 ml (3 months), 220 ml (6 months), and 220 ml (12 months). Median volumes in Group E were 140 ml (3 months), 150 ml (6 months), and 175 ml (12 months). Bowel frequency per 24 hours at three and six months postoperatively was significantly greater in Group E than in Group S or the control group. Median frequency in Group E was four times (3 months) and three times (6 months) per 24 hours. Median frequency in both Group S and the control group was two times (3 months) and two times (6 months) per 24 hours. Postoperative urgency of defecation was not found in Group S, significantly less frequent than in Group E at three months. CONCLUSION: Side-to-side anastomosis may lead to a better clinical outcome than end-to-end anastomosis for carcinoma of the upper half of the rectum in the adaptation phase.

Aged↗
PubMed1999

The effect of vaginal delivery on the pelvic floor.

This study was undertaken to determine the effects of vaginal deliveries on anorectal function, and to analyze the possible clinical, physiological, and radiological risk factors predisposing to damage of the pelvic floor musculature. We studied 25 consecutive women with a mean age of 32 years old, 3 months after vaginal delivery, 17 of whom were primiparae and 8, multiparae. The symptoms of anal incontinence were assessed, and anorectal manometry, rectal sensation, and radiological measurements of the anorectal angle and pelvic floor position at rest, on squeezing, and on straining were performed. As a control, six nulliparous women underwent the same examinations. Pelvic floor descent in both the primiparae and multiparae was significantly greater at rest and on squeezing than that in the nulliparous women. Furthermore, pelvic floor descent on straining was greater in the multiparae than in the nulliparous women (P = 0.028). An analysis of the 17 primiparae showed that prolonged duration of the second stage of labor and third-degree perineal tears were important factors predisposing to pelvic floor descent. In fact, 3 of the 17 primiparae (17%) had anal incontinence. These findings indicate that vaginal delivery may cause pelvic floor descent, an obtuse anorectal angle, and bowel symptoms.

Adult↗
PubMed1999

Serologic study of human parvovirus B19 infection in pregnancy in Japan.

OBJECTIVES: To clarify the relationship between hydrops fetalis and parvovirus outbreaks in the community, seroprevalence of B19 antibody among women of childbearing age, and adverse effects of intrauterine B19 infection. METHODS: Sera were collected from 168 cases of hydrops fetalis which were diagnosed between 1987 and 1997 in Miyagi prefecture, Japan, from 232 healthy pregnant women in 1987 and 277 healthy pregnant women in 1997 in Miyagi, and from 48 women infected with B19 during pregnancy. The sera were examined for B19 IgG and IgM antibodies by enzyme-linked immunosorbent assay and for B19 DNA by polymerase chain reaction. The number of cases of erythema infectiosum in Miyagi had been monitored each month. RESULTS: Thirteen of the 168 cases of hydrops fetalis were found to be caused by intrauterine B19 infection and 12 of the 13 cases clustered in two periods of outbreaks of erythema infectiosum in the community. The positive rates of B19 IgG antibody between 1987 and 1997 were significantly different: 33% in 1987 and 46% in 1997. Nine of the 48 women infected during pregnancy showed adverse effects of the fetus: eight hydrops fetalis and one early abortion with positive B19 DNA. The fetal death rate (>12 weeks of gestation) among them was 15% (7/48), far higher than the calculated 1% among the general population. The nine mothers with adverse fetal outcomes had contact with the infectious source at the 16 weeks of gestation or earlier. CONCLUSIONS: These data clearly showed a relationship between hydrops fetalis and parvovirus outbreaks in the community, and it may be important to follow the seroprevalence for an extrapolated period time to predict occurrence of hydrops fetalis caused by B19. Also the data indicated that the gestational week infection occurred is the most important determinant of an adverse effect to the fetus as described previously.

Adolescent↗
PubMed1999

Three-dimensional reconstruction of the incudostapedial joint with helical computed tomography.

Three-dimensional images of the incudostapedial joint (I-S joint) were reconstructed using helical computed tomography (CT). The images of the joint were most often reconstructed when threshold values were selected at -500 to -700 Hounsfield Units. These shapes were changed by choosing various threshold values. Histological examinations of the cadaver specimen indicate that these changes are due to structure of the I-S joints. We conclude that these 3-D images may be useful in assessing pathology of the I-S joint.

Ear, Middle↗
PubMed1999

Microanatomy of the cerebellopontine angle and internal auditory canal: study with new magnetic resonance imaging technique using three-dimensional fast spin echo.

OBJECTIVE: We report a new magnetic resonance imaging technique that uses three-dimensional fast spin echo and the minimum intensity projection method. Using this technique, detailed images of the cerebellopontine angle (CPA) and internal auditory canal (IAC) were obtained in normal volunteers and in patients with acoustic neuromas or hemifacial spasm. METHODS: Ten normal volunteers, 44 patients with acoustic neuromas, and 31 patients with hemifacial spasm were studied using the three-dimensional fast spin echo magnetic resonance imaging protocol. The CPA and IAC were scanned by using a 1-mm slice thickness in the axial and parasagittal planes. RESULTS: Normal anatomy was as follows. 1) The vestibulocochlear nerve was ovoid near the brain stem and changed to a slightly crescentic configuration (C shape) as it traveled laterally. 2) Separation of the cochlear and vestibular nerves was observed near the central part of the IAC. 3) Discrimination between the superior and inferior vestibular nerves was also possible near the fundus of the IAC. 4) The facial nerve was easily identifiable as a discrete nerve at the anterior aspect of the vestibulocochlear nerve. 5) The meatal loop of the cerebellar artery was located medial to the porus in 44% of 95 CPAs and reached the porus or protruded into the porus in 56%. Acoustic neuromas were as follows. 1) In a patient with a very small intracanalicular tumor, the nerve on which the tumor was located could be identified. 2) In 22 of 44 acoustic neuromas, cerebrospinal fluid was present between the tumor and the fundus of the IAC. Hemifacial spasm was as follows. The relationship between the responsible artery and the facial nerve could be precisely observed. CONCLUSION: The three-dimensional fast spin echo method offers ultrahigh-resolution images, which are extremely useful in understanding the surgical anatomy of the CPA and IAC.

Cerebellopontine Angle↗
PubMed1999

Autocrine regulation of osteoclast formation and bone resorption by IL-1 alpha and TNF alpha.

Bone resorption is regulated by the cytokines within marrow cells that mediate osteoclast formation and activation. IL-1 and TNF induce bone resorption by stimulating the production of osteoclast-like multinucleated cells and by increasing the bone-resorbing activity of formed osteoclasts. This study was designed to detect IL-1 and TNF in osteoclasts in vitro and to determine whether these cytokines up-regulate osteoclast differentiation and bone resorption. The production of IL-1 alpha, -beta, and TNF alpha, beta in osteoclasts was examined immunohistochemically and by in situ hybridization. In the co-culture of C57BL/6N mouse bone marrow and MC3T3-G2/PA6 cells, a colony of osteoclasts formed, and IL-1 alpha and TNF alpha were detected. However, IL-1 beta and TNF beta were not detected. To investigate the role of IL-1 alpha and TNF alpha from osteoclasts, we enumerated TRAP-positive cells and measured the resorption pit areas in the presence of antibodies against IL-1 alpha and TNF alpha. The addition of antibodies against IL-1 alpha and TNF alpha to the co-culture system decreased the number of TRAP-positive colonies at seven days after incubation (anti-IL-1 alpha, 25.0 +/- 2.3%; anti-TNF alpha, 41.7 +/- 3.7%; anti-IL-1 alpha + anti-TNF alpha, 40.5 +/- 1.3%; and control, 100%), and the ratio of mononuclear to multinuclear cells had changed (anti-IL-1 alpha, 90:10; anti-TNF alpha, 75:25; anti-IL-1 alpha+ anti-TNF alpha, 88:12; and control, 60:40). The total pit areas per dentin slice also decreased with the addition of antibodies (anti-IL-1 alpha, 28,828; anti-TNF alpha, 49,249; anti-IL-1 alpha + anti-TNF alpha, 30,685; and control, 303,139 mm2). These results suggest that local production of IL-1 alpha and TNF alpha by osteoclasts is an important mechanism for regulating the osteoclast differentiation and bone resorptive process.

Acid Phosphatase↗
PubMed1998

Differential diagnosis of NPH and brain atrophy assessed by measurement of intracranial and ventricular CSF volume with 3D FASE MRI.

Differential diagnosis of NPH and brain atrophy is sometimes difficult. Recently, a new method using MRI was introduced as a noninvasive, direct technique for the measurement of intracranial CSF volume. Using this new technique, we measured the intracranial and ventricle CSF volume in patients with enlarged ventricles in order to differentiate between NPH and brain atrophy. Ten healthy volunteers (control group) and 21 patients with enlarged ventricles were enrolled in this study. Eleven out of 21 patients were clinically diagnosed as having NPH (shunted group) and the remaining 10 patients were considered to have cerebral atrophy (non-shunted group). Intracranial and ventricular CSF volume in each case were measured by 3D FASE (Fast Asymmetric Spine-Echo) MR imaging sequence with region growing method. Ventricular/intracranial CSF volume ratio was also calculated. Ten out of 11 patients showed improvement in clinical symptoms and/or dementia scale after shunting. Our results clearly indicate that the ventricular volume in the shunted group was enlarged and that the ventricular/intracranial CSF ratio was significantly high. Thus we concluded that enlarged ventricle with high ventricular/intracranial CSF volume ratio strongly suggests NPH.

Adult↗
PubMed1998

Surgical treatment of Cronkhite-Canada syndrome associated with protein-losing enteropathy: report of a case.

PURPOSE: The case of a patient with Cronkhite-Canada syndrome, who developed a protein-losing enteropathy, is reported. METHODS: After localization of the protein-losing region, a right colectomy was performed. RESULTS: Hypoproteinemia and ectodermal changes improved postoperatively. CONCLUSIONS: Surgery is an effective treatment for protein-losing enteropathy in Cronkhite-Canada syndrome. Ectodermal changes improve after correcting malnutrition.

Female↗
PubMed1998

Genetic changes in primary colorectal cancer by comparative genomic hybridization.

Comparative genomic hybridization (CGH) is a powerful new technique for the molecular cytogenetic analysis of cancer. In this method, at first the cancer DNA and normal DNA are labeled with biotin and digoxigenin, respectively, and then the labeled DNAs are applied onto normal lymphocyte metaphase preparations in hybridization. After hybridization, they are stained with FITC and rhodamine, respectively, so chromosomal gains and losses in cancer are thus detected by using a green:red ratio. In this study, we analyzed the abnormal chromosomes in nine cases with human primary colon cancer. A gain in chromosomes 11p, 12q, 16p, 20p, and 20q were observed, while a loss of 18q and 22q were discovered. CGH may thus provide us with important information for analyzing the genes in colon cancer.

Chromosome Aberrations↗
PubMed1998

Presacral epidermoid cyst: report of a case.

An asymptomatic tumor in the pelvis was incidentally found by ultrasonography in a 67-year-old woman while being examined after presenting with a common cold. Further examinations revealed a presacral cystic tumor, which measured 10 x 12cm in size. The cyst was thus removed in the normal manner for such cases. The pathological diagnosis was an epidermoid cyst. An analysis of 15 other cases previously reported in the literature indicated that large epidermoid cysts should normally be excised through an abdominal approach alone, provided that the tumor is benign.

Aged↗
PubMed1998

Aberrant jugular bulb vein obstructing approach to intracanalicular vestibular schwannoma.

In cases of jugular bulb anomalies, such as a high jugular bulb, troublesome bleeding may occur during surgery. We report an unusual case with a vestibular schwannoma, in which we recognized an additional branch arising from the jugular bulb. Three-dimensional computed tomography (3-D CT) revealed this anomaly beforehand, enabling us to avert excessive bleeding upon resection of the tumour. The abnormal vein was thought to be a remnant of the petrosquamosal sinus in the embryonic stage.

Female↗
PubMed1997

Rapid internalization of exogenous ganglioside GM3 and its metabolism to ceramide in human myelogenous leukemia HL-60 cells compared with control ganglioside GM1.

Incorporation and metabolism of exogenous GM3 in human myelogenous leukemia HL-60 cells were analyzed using 3H-labeled GM3 ([3H]GM3). [3H]GM3 was rapidly internalized into the cells (trypsin-resistant fraction) 8 times more than the control, 3H-labeled GM1 ([3H]GM1). In addition, not only incorporation but also metabolism of [3H]GM3 was more rapid than [3H]GM1 in HL-60 cells. Moreover, one of the metabolites was found to co-migrate with ceramide in thin-layer chromatography analysis and ceramide formation from exogenous GM3 is more rapid than that from exogenous GM1. These results suggested that there would be some preferential mechanism to produce ceramide from differentiation-inducible GM3 in HL-60 cells rather than from non-inducing GM1.

Cell Membrane↗
PubMed1997

Recurrent colonic cancer developing at the site of a stapled stump: report of a case.

We report herein the case of a 54-year-old woman who developed a recurrence of carcinoma in a stapled colon stump 2 years after undergoing an anterior resection for carcinoma of the rectosigmoid colon. At this time an end to end anastomosis (EEA) stapler had been used to perform a side-to-end anastomosis. The implantation of cancer cells was thought to have caused the recurrence.

Anastomosis, Surgical↗