Biomedical subjects

T Takasaka

Publications and source records attributed to T Takasaka.

At least 37 records · Page 2Linked to original sources

PubMed2000

A case of extramedullary plasmacytoma arising from the nasal septum.

A rare case of extramedullary plasmacytoma arising from the nasal septum with localized amyloid deposition is reported. A 75-year-old woman presented with a history of post-nasal discharge and nasal obstruction for several months. Endonasal endoscopic observation revealed the presence of a mass arising from her nasal septum with an extension to the nasopharynx. No cervical lymph nodes were palpable. The biopsy specimen was diagnosed as a plasmacytoma (IgG, lambda-light chain type). Both serum myeloma-protein and urine Bence-Jones protein were negative. Bone marrow biopsy, a chest radiograph, total body skeletal survey and 67Ga- and 99mTc-scintigrams showed no other systemic lesions. These findings confirmed the diagnosis of extramedullary plasmacytoma in the nasal septum. The patient received irradiation of 40 Gy without clinically detectable reduction of tumour size. The patient eventually underwent complete resection of the tumour by KTP/532 laser under endonasal endoscopic control. Pathologically, the tumour mass was composed mainly of amyloid deposition with a marked reduction of tumour cells. This indicated the radiosensitiveness of tumour cells, which was clinically masked by the increased amyloid deposition. The clinical presentation, pathological features and surgical procedures are described with a review of the literature.

Aged↗

PubMed2000

A case report of sinonasal teratocarcinosarcoma.

A sinonasal teratocarcinosarcoma (SNTCS) is a rare and aggressive malignant neoplasm histologically characterized by the combination of one or more epithelial elements and mesenchymal components. We report a case of a 78-year-old man with SNTCS involving the nasal cavity and paranasal sinuses. He complained of epiphora and exophthalmos with weight loss. Physical and diagnostic images resulted T4N0M0. The tumor was completely and widely resected via a trans-facial approach to perform total maxillectomy with orbital exenteration. The clinical presentation, pathologic features, and clinical course are described with a review of the literature.

Aged↗

PubMed2000

The time-course of the effects of contralateral sound on the level of distortion product otoacoustic emissions.

The effects of the addition of contralateral noise on the level of distortion product otoacoustic emissions (DPOAEs) were examined. In the present study, the DPOAEs were recorded for a relatively long period (2 minutes), and the time-course of the effects of contralateral sound on the level of DPOAEs were considered. In general, the addition of the contralateral noise resulted in suppression of the level of DPOAEs. The time-course of this suppression appeared to depend on the level of the contralateral noise. When the level of the contralateral noise was low, the suppression of the level of DPOAEs seemed to be largely unchanged for at least 2 minutes. In contrast, when a relatively high level of contralateral noise was used, the suppression of the level of DPOAEs decreased with time.

Acoustic Stimulation↗

PubMed2000

Long-term follow-up of obstructive sleep apnea syndrome following surgery in children and adults.

Obstructive sleep apnea syndrome (OSAS) is characterized by recurrent apneas during sleep, resulting in repetitive hypoxemia. The present study retrospectively analyzed subjective and objective assessments of the patients with OSAS in a relatively long-term follow-up. From February 1986 to August 1996, 53 patients received surgical treatment for OSAS and snoring. Thirty-seven (27 males and 10 females) out of 53 patients completed the questionnaire and postoperative sleep study was obtained in 6 patients. In 20 children (<15 years), snoring, sleep apnea, and daytime sleepiness completely disappeared in 12, 19, and 16, and improved in 8, 1, and 4, respectively. These findings confirm that tonsillectomy and/or adenoidectomy in children may be the first selection for treatment. In 17 adults, snoring, sleep apnea, and daytime sleepiness completely disappeared in 2, 5, and 8, improved in 11, 8, and 7, and was unchanged in 4, 4, and 1, respectively. The apnea index in adults was significantly decreased in both early and late postoperative periods. These results suggest that surgery is a satisfactory alternative for adult patients if performed accurate preoperative diagnosis of the localization of the airway collapse and careful long-term follow-up.

Adenoidectomy↗

PubMed2000

Streptococcus anginosus in head and neck squamous cell carcinoma: implication in carcinogenesis.

It has been suggested that Helicobacter pylori (H. pylori) infection might be associated with not only gastric ulcers but also gastric malignancies. Recently, it was reported that the Streptococcus anginosus (S. anginosus) DNA sequence was found in DNA samples extracted from esophageal cancers. Because smoking and alcohol abuse are regarded as risk factors for both esophgeal cancer and head and neck cancer, infection of S. anginosus might be associated with carcinogenesis of head and neck cancer. To investgate the involvement of S. anginosus infection in head and neck cancer, we analyzed 217 DNA samples prepared from head and neck squamous cell carcinomas. We performed PCR analysis with S. anginosus-16S ribosomal DNA-specific primers, and Southern blot analysis. For detection of S. anginosus in the oral and pharyngeal cavities, we used oropharyngeal bacteriological culture and PCR analysis of gingival smears of the patients. By PCR analysis, the S. anginosus DNA sequence was found in 217 out of 217 (100%) DNA samples obtained from head and neck cancers. By Southern blot analysis, positive bands were detected in 41 out of 125 (33%) samples. We could find no S. anginosus colony in oropharyngeal bacteriological culture dishes of 53 patients with and without head and neck cancer. On the other hand, we found the S. anginosus DNA fragment in 8 out of 8 DNA samples obtained from gingival smears by PCR analysis. These data indicate that the upper aerodigestive environment of the patients permitting S. anginosus infection was implicated in the carcinogenesis of head and neck squamous cell carcinoma.

Adult↗

PubMed1999

Dynamic Ca2+ signalling in rat arterial smooth muscle cells under the control of local renin-angiotensin system.

1. We visualized the changes in intracellular Ca2+ concentration ([Ca2+]i), using fluo-3 as an indicator, in individual smooth muscle cells within intact rat tail artery preparations. 2. On average in about 45 % of the vascular smooth muscle cells we found spontaneous Ca2+ waves and oscillations ( approximately 0.13 Hz), which we refer to here as Ca2+ ripples because the peak amplitude of [Ca2+]i was about one-seventh of that of Ca2+ oscillations evoked by noradrenaline. 3. We also found another pattern of spontaneous Ca2+ transients often in groups of two to three cells. They were rarely observed and are referred to as Ca2+ flashes because their peak amplitude was nearly twice as large as that in noradrenaline-evoked responses. 4. Sympathetic nerve activity was not considered responsible for the Ca2+ ripples, and they were abolished by inhibitors of either the Ca2+ pump in the sarcoplasmic reticulum (cyclopiazonic acid) or phospholipase C (U-73122). 5. Both angiotensin antagonists ([Sar1,Ile8]-angiotensin II and losartan) and an angiotensin converting enzyme inhibitor (captopril) inhibited the Ca2+ ripples. 6. The extracellular Ca2+-dependent tension borne by unstimulated arterial rings was reduced by the angiotensin antagonist by approximately 50 %. 7. These results indicate that the Ca2+ ripples are generated via inositol 1,4, 5-trisphosphate-induced Ca2+ release from the intracellular Ca2+ stores in response to locally produced angiotensin II, which contributes to the maintenance of vascular tone.

1-Sarcosine-8-Isoleucine Angiotensin II↗

PubMed1999

Expression of connexin 26 and Na,K-ATPase in the developing mouse cochlear lateral wall: functional implications.

The immunohistochemical localization of connexin 26 (a gap junction protein) and Na,K-ATPase in the mouse cochlear lateral wall was studied at different ages between 0 and 30 days after birth (DAB). Connexin 26-like immunoreactivity was sparsely distributed among the connective tissue cells just lateral to the future marginal cells of the stria vascularis on 0 DAB. In the mice of 3-6 DAB, connexin 26 was observed in the strial basal cell area, and was increased in its distribution density on 10 DAB. Connexin 26 was sparsely distributed among the fibrocytes in the spiral ligament and the suprastrial zone on 10 DAB, and its distribution density increased rapidly in the mouse on 12 DAB. The immunohistochemical distribution reached the adult pattern in the cochlear lateral wall on 15 DAB. Weak Na, K-ATPase-like immunoreactivity was observed in the epithelial cells, corresponding to the future strial marginal cells, on 0 DAB. Its staining intensity was enhanced with the increase of age, and reached the adult pattern on 10 DAB. In contrast, Na,K-ATPase-like immunoreactivity in the type II fibrocytes and suprastrial fibrocytes was first detected on 12 DAB, and reached the mature level on 15 DAB. It is well known that the endolymphatic potential (EP) reaches the adult level 2 weeks after birth. The expression patterns of connexin 26 and Na,K-ATPase in the fibrocytes of the spiral ligament and the suprastrial zone coincided with the rapid growth and maturation of EP. These findings may suggest a role for the gap junctional communications and Na,K-ATPase activity of the fibrocytes within the cochlear lateral wall in the generation and maturation of EP.

Age Factors↗

PubMed1999

Altered cochlear fibrocytes in a mouse model of DFN3 nonsyndromic deafness.

DFN3, an X chromosome-linked nonsyndromic mixed deafness, is caused by mutations in the BRN-4 gene, which encodes a POU transcription factor. Brn-4-deficient mice were created and found to exhibit profound deafness. No gross morphological changes were observed in the conductive ossicles or cochlea, although there was a dramatic reduction in endocochlear potential. Electron microscopy revealed severe ultrastructural alterations in cochlear spiral ligament fibrocytes. The findings suggest that these fibrocytes, which are mesenchymal in origin and for which a role in potassium ion homeostasis has been postulated, may play a critical role in auditory function.

Animals↗

PubMed1999

Endoscopic endonasal repair of orbital floor fracture.

BACKGROUND: High-resolution endoscopes and the advent of endoscopic instruments for sinus surgery provide surgeons with excellent endonasal visualization and access to the orbital walls. OBJECTIVE: To demonstrate repair of orbital floor blowout fractures through an intranasal endoscopic approach that allows repair of the orbital floor fracture and elevation of the orbital content using a balloon catheter without an external incision. DESIGN: This study was a retrospective analysis of 11 patients who underwent surgical repair of orbital floor fractures from September 1994 to June 1997. There were 10 male patients and 1 female patient, aged 12 to 32 years (mean age, 24 years). These patients had undergone primary repair of pure orbital blowout fractures and were followed up at least 6 months after surgery. RESULTS: There were no intraoperative or postoperative complications. Nine patients showed a complete improvement of their diplopia. Two patients with posterior fractures showed persistent diplopia, which was well managed by prisms. CONCLUSION: Endoscopic repair of the orbital floor blowout fracture using an endonasal approach appears to be a safe and effective technique for the treatment of diplopia.

Adolescent↗

PubMed1999

Expression and localization of the Na+-H+ exchanger in the guinea pig cochlea.

Physiological studies have shown that the Na+-H+ exchanger (NHE) is a major carrier protein regulating the intracellular pH in the cells of the cochlea. The presence of multiple forms of the exchanger has been demonstrated by the recent cloning of four mammalian NHEs, NHE-1 to NHE-4. Despite the structural similarity, these NHE isoforms differ in their tissue distribution, kinetic characteristics, and responses to external stimuli. The present study was undertaken to examine the expression and distribution of four NHE isoforms in the guinea pig cochlea. We used reverse transcription-polymerase chain reaction to assess the expression of NHE-1-4 isoforms and non-radioactive in situ hybridization to examine their localization. Although NHE-2, -3 and -4 isoform mRNAs could be detected in the cochlear tissue, the NHE-1 message was predominant. Cloned guinea pig NHE-1-4 partial cDNA fragments were highly homologous to the corresponding rat NHE isoforms. NHE-1 isoform mRNA was distributed in the hair cells, marginal cells, spiral ligament fibrocytes, spiral prominence cells and spiral ganglion cells. NHE- localized in a variety of cochlear cells would contribute to their differential function.

Amino Acid Sequence↗

PubMed1999

Kinin and histamine stimulate Cl- secretion in gerbil middle ear epithelium: connection to otitis media.

The effects of bradykinin (BK) and histamine on transepithelial ion transport in primary cultures of gerbil middle ear epithelium were investigated. Lysyl-bradykinin (lys-BK) elicited a transient increase in short-circuit current (I(sc)) when added to apical or basolateral surfaces. Lys-BK had a larger effect than BK or des-arg9-BK on both epithelial surfaces. Histamine induced a transient increase in I(sc) only when added to the basolateral surface. Mepyramine, an H1 histamine antagonist, greatly reduced the histamine-induced I(sc). The H2 and H3 histamine antagonists were both ineffective for inhibiting the I(sc) responses to histamine. Diphenylamine-2-carboxylate or 4,4'-diisothiocyanostilbene-2,2'-disulfonic acid, Cl- channel blockers, significantly blocked the I(sc) responses to lys-BK or histamine. The Ca2+-mobilizing action of lys-BK and histamine was also investigated in single middle ear epithelial cells. BK and histamine induced an increase in the intracellular Ca2+ concentration. 1,2-Bis-(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid-acetoxymethyl ester, a calcium chelator, greatly reduced the increase in the I(sc) responses to lys-BK or histamine. These data indicate that BK and histamine activate intracellular Ca2+-dependent mechanisms, leading to apical Cl- secretion in the cultured gerbil middle ear epithelium via B2 BK receptors and H1 histamine receptors.

Animals↗

PubMed1999

Prognosis of sudden deafness with special reference to risk factors of microvascular pathology.

OBJECTIVE: We attempted to elucidate the contribution of microvascular disorders as risk factors to the prognostic outcome in well-defined patients with sudden deafness. METHODS: One-hundred and thirty-two patients diagnosed as unilateral sudden deafness were retrospectively analyzed. Auditory function was determined by pure-tone audiometry. Diabetes, hyperlipidemia, and hypertension were considered as microvascular diseases. RESULTS: Concurrent microvascular diseases were recognized in 38 patients. Although the hearing disturbance at the first visit showed no difference from patients without concurrent diseases, a better outcome of hearing was obtained in patients without the concurrent diseases. CONCLUSION: The poor prognosis observed in patients with the concurrent diseases is likely to have been brought about by preexisting microvascular disease of the hearing organ, which is highly affected by aging.

Adult↗

PubMed1999

Unilateral examination of olfactory threshold using the Jet Stream Olfactometer.

OBJECTIVE: The Jet Stream Olfactometer, a modification by the T&T olfactometer, has been recently developed and is now commercially available. This Jet Stream Olfactometer can routinely measure the unilateral sense of smell. Clinical usefulness of the Jet Stream Olfactometer was evaluated. METHODS: Twenty-three patients with sinus-related symptoms were examined. Unilateral olfactory acuity was examined using the Jet Stream Olfactometer and compared it with the anatomy of the olfactory cleft by computed tomographic (CT) scans. RESULTS: In 13 of the 23 patients examined the right olfactory threshold was similar to that of the left. Of these 13, in seven patients there was transport damage of the odorants and in the other six there was sensorineural damage. Ten patients showed an apparent difference between the right and left smell thresholds. Anosmia in seven of these ten patients was due to a conductive olfactory disturbance resulting from rhinosinusitis, whereas sensorineural damage was recognized in the other three patients. The difference in the detection threshold between the right and left nasal cavities was well correlated to that of the opacity between the right and left olfactory clefts. CONCLUSION: Jet Stream Olfactometer provides a convenient and reliable means for assessing the ability of unilateral smell.

Adult↗

PubMed1999

IL-12 receptor beta2 and CD30 expression in paranasal sinus mucosa of patients with chronic sinusitis.

The aetiology of chronic sinusitis is still poorly understood. The expression of T-helper 1 (Th1) and T-helper 2 (Th2) cell markers, interleukin (IL)-12 receptor beta2 subunit (IL-12Rbeta2) messenger ribonucleic acid (mRNA) and CD30, respectively, were investigated in the paranasal sinus mucosa of patients with chronic sinusitis in an attempt to elucidate the involvement of Th1 and Th2 cells in this disease. Anterior ethmoidal mucosae were surgically obtained from two groups of patients with chronic sinusitis: those who had allergic rhinitis (allergic group, n=11) and those without allergy (nonallergic group, n=11). IL-12Rbeta2 mRNA was quantified by means of the reverse transcription polymerase chain reaction, and CD30-positive cells were examined immunohistochemically. Both IL-12Rbeta2 mRNA and CD30 were expressed in the sinus mucosa of the allergic and nonallergic groups. The proportion of mononuclear cells which were CD30-positive in the sinus mucosa was significantly greater in the allergic than in the nonallergic group. The expression levels of IL-12Rbeta2 mRNA were virtually equivalent in both groups. These results suggest a T-helper 2-dominated mucosal reaction in the allergic compared to the nonallergic group, and indicate T-helper 1 activity in the sinus mucosa of both groups. The ubiquity of T-helper 1 cells suggests that they play a role in maintaining local mucosal defences against foreign antigens, which continually enter the upper respiratory tract.

Chronic Disease↗

PubMed1999

Increased carbon monoxide in exhaled air of patients with seasonal allergic rhinitis.

BACKGROUND: Carbon monoxide (CO) can be detected in exhaled air and is increased in asthmatic patients. However, it is uncertain whether exhaled CO is increased in patients with allergic rhinitis. OBJECTIVE AND METHODS: To study whether exhaled CO is increased in patients with allergic rhinitis, exhaled CO concentrations were measured on a CO monitor by vital capacity manoeuvre in 86 patients with seasonal allergic rhinitis during and out of the cedar pollen season. RESULTS: During the season, exhaled CO concentrations were 3. 6 +/- 0.3 p.p.m. and decreased to 1.2 +/- 0.1 p.p.m. out of the season. The values of exhaled CO out of the season were similar to those in age-matched non-smoking healthy control subjects (1.2 +/- 0. 1 p.p.m.). Exhaled CO concentrations were significantly higher in patients with symptoms than in those without symptoms (P < 0.01). Exhaled CO concentrations in patients did not differ significantly among oral and nasal exhalation, and oral exhalation with an expiratory resistance (P > 0.20). CONCLUSION: These findings suggest that allergic rhinitis increases the concentration of CO in exhaled air and increases in exhaled CO may be derived from lower airways.

Adult↗

PubMed1999

Hearing loss with a mitochondrial gene mutation is highly prevalent in Japan.

OBJECTIVES/HYPOTHESIS: Mutations in the mitochondrial genome may predispose people to sensorineural hearing loss. An adenine to guanine point mutation in the tRNA(Leu(UUR)) gene at nucleotide 3,243 is one of the deaf-related mutations. This mutation is reported to be associated with 0.9% of diabetes mellitus patients. However, the prevalence of this mutation in hearing-impaired patients still remains unknown. The aim of this study was to determine the prevalence of this mutation among bilaterally sensorineural hearing-impaired patients in Japan. STUDY DESIGN: Retrospective survey of 100 patients with bilateral sensorineural hearing loss without any evident causes. METHODS: Mitochondrial DNA fragments from the patients were amplified by polymerase chain reaction, followed by a restriction enzyme fragment length polymorphism method. RESULTS: Three patients with this mutation were identified. Their clinical profiles were different from the category which had been considered as hearing loss caused by this mitochondrial gene mutation. CONCLUSIONS: The mutation is associated with approximately 3% of bilateral sensorineural hearing loss cases of unknown origin and is possibly distributed widely in sensorineural hearing-impaired patients in Japan.

Adult↗

PubMed1999

Inhibitory effect of erythromycin on interleukin-8 secretion from exudative cells in the nasal discharge of patients with chronic sinusitis.

OBJECTIVES: The mechanism of the efficacy of long-term low-dose macrolide therapy for chronic sinusitis is not fully understood. The authors studied the inhibitory effect of erythromycin on interleukin-8 (IL-8) secretion from exudative cells in the nasal discharge of patients with chronic sinusitis. STUDY DESIGN AND METHODS: Exudative cells in the nasal discharge were isolated from six patients with nonallergic chronic sinusitis. The cells, more than 90% of which were neutrophils, were incubated with or without erythromycin in the presence of 10 micrograms/mL of lipopolysaccharide. The IL-8 concentrations in the culture supernatants were measured by enzyme-linked immunoassay. RESULTS: The amount of secreted IL-8 in the absence of erythromycin was 682 +/- 226 pg/10(6) cells/24 h. The IL-8 secretion was significantly reduced to 66 +/- 15% and 46 +/- 13% of the control in the presence of 10(-6) and 10(-5) M of erythromycin, respectively. CONCLUSION: Erythromycin may act as a biologic modulator that inhibits IL-8 secretion from exudative cells and thereby blocks the vicious circle of neutrophil recruitment and IL-8 generation in the inflammatory site in chronic sinusitis.

Anti-Bacterial Agents↗

PubMed1999

Profound hearing loss attributable to cochlear nerve disease: diagnosis with combination of otoacoustic emission and magnetic resonance imaging.

OBJECTIVE: To detect the causes of deafness based on the combined findings of auditory brainstem response (ABR), distortion product otoacoustic emissions (DPOAEs), and three-dimensional Fourier transformation-constructive interference in steady state (3DFT-CISS) magnetic resonance imaging (MRI). STUDY DESIGN: Retrospective review of the medical records of 13 patients with unilateral profound hearing loss since childhood. METHODS: Subjects were tested with pure-tone audiometry, ABR, DPOAEs, and 3DFT-CISS imaging. RESULTS: No significant components of ABR were observable in any of the deaf ears. In 10 cases, the cochlear nerves of the deaf ears were found to be as normal as the healthy sides by 3DFT-CISS imaging, and no significant levels of DPOAEs were recorded. In the other three cases, no apparent cochlear nerves were identified by 3DFT-CISS imaging. Although no significant levels of DPOAEs were observable in two cases with cochlear nerves invisible by the MRI study, almost the same level of DPOAEs as that in the healthy side was recorded in the last case. CONCLUSIONS: In the last particular case, the cochlear nerve seemed to be mainly responsible for the profound deafness. 3DFT-CISS imaging in combination with preexisting audiological measures may provide direct evidence for the cochlear nerve disease. steady state, internal auditory canal, cochlear nerve disease.

Audiometry, Pure-Tone↗