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Biomedical subjects

K Tsunoda

Publications and source records attributed to K Tsunoda.

At least 19 recordsLinked to original sources
PubMed2006

Head torsion technique for detailed observation of larynx and hypopharynx.

We introduce here an easy but effective method for detailed observation of the larynx and hypopharynx. During the endoscopic observation, the patient's head is turned to one side. Anatomical structures on the same side of the endolarynx, such as the laryngeal ventricle and inferior surface of the vocal fold, are easily observed. In addition, observation of the opposite side of the hypopharynx also becomes easier. Such head turning is also useful in patients with an oblique larynx, in whom the epiglottis obstructs insertion of the endoscope. This is a simple but very effective technique for laryngeal and hypopharyngeal observation.

Endoscopy↗
PubMed2004

A mouse model of pemphigus vulgaris by adoptive transfer of naive splenocytes from desmoglein 3 knockout mice.

BACKGROUND: Pemphigus vulgaris (PV) is an autoimmune blistering disease caused by antidesmoglein3 (anti-Dsg3) IgG autoantibodies. Recently, we developed a PV mouse model by adoptive transfer of splenocytes from recombinant Dsg3-immunized Dsg3(-/-) mice to Rag2(-/-) immunodeficient mice that expressed Dsg3. OBJECTIVES: We determined whether the adoptive transfer of naive splenocytes from nonimmunized Dsg3(-/-) mice induces the anti-Dsg3 IgG production and the PV phenoytpe in recipient mice. METHODS: We adoptively transferred naive Dsg3(-/-) splenocytes into Rag2(-/-) mice and compared their PV phenoytpe with those mice receiving immunized Dsg3(-/-) splenocytes. The numbers of splenocytes and their subpopulations required for anti-Dsg3 IgG production were examined. RESULTS: Mice that received naive Dsg3(-/-) splenocytes produced anti-Dsg3 IgG, which bound to keratinocyte cell surfaces in vivo, and developed the PV phenotype, including oral erosions with suprabasilar acantholysis. Antibody production and the appearance of the PV phenotype were delayed by approximately 2 weeks in mice that received naive splenocytes compared with mice that received immunized splenocytes. However, once the PV phenotypes developed, there were no apparent differences in disease severity between the two models. Interestingly, the anti-Dsg3 IgG titres were significantly lower in mice that received naive splenocytes than in mice that received immunized splenocytes, suggesting that the former antibodies were more potent than the latter. The frequency of anti-Dsg3 IgG production depended on the number of transferred naive splenocytes. Both CD4+ T cells and B220+ B cells from naive Dsg3(-/-) mice were essential for the production of anti-Dsg3 IgG antibodies. CONCLUSIONS: Dsg3-specific naive lymphocytes in Dsg3(-/-) mice can be primed and activated by the endogenous Dsg3 in recipient mice to produce pathogenic anti-Dsg3 IgG without active immunization. This approach using naive lymphocytes provides a unique model to dissect immunological mechanisms of tolerance against peripheral autoimmune targets.

Adoptive Transfer↗
PubMed2001

A high-efficiency cross-flow micronebulizer interface for capillary electrophoresis and inductively coupled plasma mass spectrometry.

A pneumatic nebulizer interface for capillary electrophoresis (CE) and inductively coupled plasma mass spectrometry (ICPMS) is reported. The interface is constructed using a high-efficiency cross-flow micronebulizer (HECFMN) and has the following features. (1) Makeup solutions can be fed to the interface by nebulizer self-aspiration and liquid gravity pressurization. (2) The liquid dead volume of the interface is approximately 65 nL, much smaller than those (200-2500 nL) reported for other interfaces. (3) The interface can be stably operated at a liquid flow rate down to 5 microL/min with a high analyte transport efficiency up to 95% to the plasma and (4) does not induce noticeable laminar flow in the CE capillary at typical nebulizer gas flow rates of 0.8-1.2 L/min. Because of these features, baseline resolution of 10 lanthanides with a CE-ICPMS system using the HECFMN interface is achieved, and detection limits and peak asymmetry are 0.05-1 microg/L and 0.93-1.23, respectively, improved significantly over those reported previously for a CE-ICPMS system using a high-efficiency nebulizer interface. Peak precision for the 10 lanthanides is in the range of 6.2-12.3% RSD (N = 5). Peak widths are from 9.1 s for 139La to 17.9 s for 175Lu. The effects of nebulizer gas flow rate, makeup solution flow rate, and spray chamber volume on CE-ICPMS signal intensity and separation are also evaluated for the HECFMN interface by the separation of Cr3+ and Cr2O7(2-).

Journal Article↗
PubMed2001

A high-efficiency cross-flow micronebulizer for inductively coupled plasma mass spectrometry.

A pneumatically driven, high-efficiency cross-flow micronebulizer (HECFMN) is introduced for inductively coupled plasma (ICP) spectrometries. The HECFMN uses a smaller nozzle orifice for nebulizer gas (75 microm in diameter) and a replaceable and adjustable fused-silica capillary for sample uptake. The HECFMN is optimally operated over a wide range of sample uptake rate (5-120 microL/min) at a rf power of 1100 W and nebulizer gas flow rates of 0.8-1.0 L/min when a 50 microm i.d. by 150 microm o.d. capillary is used. The aerosol quality is qualitatively examined in a simple manner, and the transport efficiencies are determined by direct filter collection. Compared with conventional cross-flow nebulizers (CFNs), the HECFMN produces much smaller and more uniform droplets and thus provides much higher analyte transport efficiencies (generally 24-95%) at the sample uptake rates of 5-100 microL/min. Several analytical performance indexes are acquired using an Ar ICPMS system. The sensitivities and detection limits measured with the HECFMN at 50 microL/min sample uptake rate are comparable to or improved over those obtained with a conventional CFN consuming 1 mL/min sample, and the precisions with the HECFMN (typically 1.1-1.7% RSDs) are slightly better than those with the CFN (1.6-2.3% RSDs). The ratios of refractory oxide ion-to-singly charged ion (CeO+/Ce+) are typically in the range from 0.7 to 3.3% for the sample uptake rates of 5-100 microL/min. The free aspiration rate of the HECFMN is 8.9 microL/min for distilled deionized water at the nebulizer gas flow rate of 1.0 L/min without any effect of pressure. The features of the HECFMN suggest good potential for HECFMN use in interfacing ICPMS with capillary electrophoresis and microcolumn high-performance liquid chromatography.

Journal Article↗
PubMed2001

Single nucleotide polymorphism (D68D, T to C) in the syntaxin 1A gene correlates to age at onset and insulin requirement in Type II diabetic patients.

AIM/HYPOTHESIS: Syntaxin 1A is a candidate gene for Type II (non-insulin-dependent) diabetes mellitus, because it plays an important role in insulin secretion from the islet beta cells. We aimed to scan this gene for mutations or genetic markers that correlate with Type II diabetes. METHODS: We identified and characterized coding exons of the syntaxin 1A gene and scanned the newly identified 10 exons using direct sequencing. RESULTS: In the single nucleotide polymorphism (SNP) of exon 3 (D68D, T to C) among three newly identified SNPs, genotype frequency of the homozygote of C allele (CC) occurred more frequently in a Type II diabetic group than in a non-diabetic group (16.48 %, n = 182, vs 11.05 %, n = 181, p = 0.0499). Among the diabetic patients, age of onset in patients with CC genotype was lower than that in patients with the TT and TC genotypes [40.10 +/- 1.50 years old (means +/- SEM) vs 44.20 +/- 0.58, p = 0.005]. Patients with the CC genotype had a higher frequency of insulin treatment (78.30 % vs 46.80 %, p = 0.006) with a duration equal to, or longer than, 10 years. Multiple regression analysis confirmed that the genotype was significantly and independently associated with age at onset and mode of treatment, respectively. CONCLUSION/INTERPRETATION: These data indicate that the SNP in the syntaxin 1A gene (D68D, T to C) correlates to the age of onset and insulin requirements of Type II diabetic Japanese patients.

Age of Onset↗
PubMed2001

Specific frequency distribution of erythrocytic X-protein alleles in indigenous sheep populations in East Asia.

The nonhemoglobin erythrocytic X-protein polymorphism consisting of two phenotypes called X-positive [X(+)] and X-negative [X(-)] was determined in 576 unrelated healthy native sheep of East Asia, using one-dimensional and horizontal starch gel electrophoresis. A striking difference in the frequency of the X allele coding dominantly for the X(+) type between the northern and southern populations of native East Asian sheep divided by the boundary of the Himalaya Mountains was seen (P < 0.0001). The X allele frequency ranged from 0 to 0.0438 with an average of 0.0323 in the northern population examined, consisting of the Bhyanglung, Baruwal, Yunnan, and Khalkhas sheep belonging to the Tibetan and Mongolian sheep groups. In contrast, the frequency of the same allele was in the range of 0.2037-0.4655 and the mean frequency was 0.2998 in the southern population tested, consisting of the Bengal, Kagi, Lampuchhre, Vietnamese, and Myanmar sheep, which belong to the Indian sheep group. This finding suggests that the X allele appears to be an Indian sheep marker and is potentially important in phylogenetic studies on native sheep populations, especially in East Asia.

Alleles↗
PubMed2001

Complex objects are represented in macaque inferotemporal cortex by the combination of feature columns.

Intrinsic signal imaging from inferotemporal (IT) cortex, a visual area essential for object perception and recognition, revealed that visually presented objects activated patches in a distributed manner. When visual features of these objects were partially removed, the simplified stimuli activated only a subset of the patches elicited by the originals. This result, in conjunction with extracellular recording, suggests that an object is represented by a combination of cortical columns, each of which represents a visual feature (feature column). Simplification of an object occasionally caused the appearance of columns that were not active when viewing the more complex form. Thus, not all the columns related to a particular feature were necessarily activated by the original objects. Taken together, these results suggest that objects may be represented not only by simply combining feature columns but also by using a variety of combinations of active and inactive columns for individual features.

Action Potentials↗
PubMed2001

Autologous transplantation of fascia into the vocal fold: long-term results of a new phonosurgical technique for glottal incompetence.

OBJECTIVES: To study the long-term results of autologous transplantation of fascia into the vocal fold, and to evaluate our use of autologous transplantation instead of bovine collagen injection in cases of glottal incompetence. STUDY DESIGN: Retrospective study of the patients who have undergone autologous fascia transplantation using our new technique. METHODS: Follow-up studies were performed for at least 1 year (up to 3 y) on 9 autologous fascia transplant patients (6 cases with type 1 procedures and 3 cases with type 2 procedures). Clinical observations, including laryngeal stroboscopy, and measurement of maximum phonation time (MPT) were carried out. RESULTS: During 3 months after autologous fascia transplantation, MPT gradually increased and stroboscopy showed improved glottal closure. These improvements continued beyond 1 year in all cases of type 1 surgery and 2 of 3 cases of type 2 surgery. CONCLUSIONS: Autologous transplantation of fascia into the vocal folds as a phonosurgical treatment for glottal incompetence yields excellent long-term results. Temporal fascia appears to be a highly suitable tissue for transplantation in Reinke's space. However, the fascia is less suitable for transplantation in the muscle. We speculate that transplantation of temporal fascia leads to regeneration of vocal fold tissue, perhaps using a mechanism similar to stem cell transplantation in other organs.

Adult↗
PubMed2001

Sensorineural hearing loss as the initial manifestation of polyarteritis nodosa.

A 74-year-old male was referred for the sudden onset of bilateral sudden deafness. The patient had no history of any disease or trauma to the head. Pure tone audiometry revealed bilateral moderate, to severe, sensorineural hearing loss. Auditory brain stem responses (ABRs) showed normal peak and interpeak latencies. These audiological findings suggested that his hearing loss could be attributed to inner ear lesions. However, we felt an alternative explanation for this sudden deafness was likely to exist because the patient also had a month-long fever of unknown origin (FUO) and weight loss of 5 kg/month. Using the criteria of The American College of Rheumatology, we made the diagnosis of polyarteritis nodosa (PAN). Serum MPO-ANCA was positive (x 661). For treatment, the patient was begun on prednisolone and cyclophosphamide. Nine months later, fever, hypertension, nephritis, pneumonitis, and arthritis had completely resolved, the MPO-ANCA became negative (MPO-ANCA < x 10). Furthermore, his hearing improved.

Acute Disease↗
PubMed2001

Highly sensitive and direct detection of DNA fragments using a laser-induced capillary vibration effect.

A pulsed laser-induced stationary wave capillary vibration detection method was applied to the sensitive detection of capillary gel electrophoresis, and the direct detection of non-labeled nucleic acids, such as DNA sequencing products, was demonstrated. An excimer laser operating at 248 nm was used as a CVL excitation source, and polynucleotides were sensitively detected without derivatization. From an investigation on the endurance of several matrixes to pulsed laser irradiation, a polyacrylamide without a cross-linker (0%C) was found to have adequate endurance, and it exhibited no serious damage during an analysis. A cytosine-terminated sequence reaction product was detected with a sensitivity close to that of laser-induced fluorometry (LIF). These results suggest the feasibility of the highly sensitive detection of ultramicro amounts of biological materials without a pre- or post-column derivatization, which has usually been required in sensitive detection procedures, such as LIF. Furthermore, the feasibility of a novel DNA sequencing method is also suggested.

Acrylic Resins↗
PubMed2000

Immunohistochemical expression of Ets-1 transcription factor and the urokinase-type plasminogen activator is correlated with the malignant and invasive potential in meningiomas.

BACKGROUND: The Ets-1 transcription factor has been proposed to play an important role in the invasive process of tumor cells through the induction of urokinase-type plasminogen activator (u-PA). METHODS: Because meningiomas are potentially invasive tumors, irrespective of their malignancy grades, the authors immunohistochemically investigated Ets-1 and u-PA expression in tissues obtained from 50 benign (16 meningotheliomatous, 14 fibrous, 13 transitional, 6 angiomatous, and 1 microcystic), 4 atypical, and 6 anaplastic meningiomas and correlated their results with the malignancy and invasive potential. RESULTS: Ets-1 protein was expressed in 19 of the benign meningiomas (38%)whereas 31 (62%) were u-PA positive. The percentage of positive cells frequently was < 50%. In contrast, Ets-1 and u-PA expression was observed in all 4 atypical (100%) and all 6 anaplastic (100%) cases, respectively. The proportion of cells positive for Ets-1 and u-PA frequently were > or = 50%. A significant difference was observed between Ets-1 and u-PA expression in benign and high grade meningiomas (P < 0.0001). Moreover, Ets-1 expression was found to correlate significantly with u-PA positivity in meningiomas (P < 0.0001). Twenty-one of 60 meningioma cases (35%) showed infiltration either to the brain, dura mater, or bone. Eighteen of these 21 cases (85.7%) were positive for Ets-1 and u-PA. Ets-1 and u-PA positivity was found to correlate well with the invasive phenotype in meningiomas (P < 0.001). CONCLUSIONS: The findings of the current study support the possibility that the Ets-1 transcription factor, through u-PA induction, may be involved in the invasive process in meningiomas.

Blotting, Western↗
PubMed2000

Effect of Zena F-III, a liquid nutritive and tonic drug, on the neurochemical changes elicited by physical fatigue in mice.

The effects of a liquid nutritive and tonic drug (NTD) on the neurochemical changes elicited by physical fatigue in mice were investigated in terms of the calcium-dependent dopamine synthesizing function of the brain. In this study, Zena F-III (Taisho Pharmaceutical Co., Ltd., Japan), one of the most popular NTDs in Japan, containing 15 crude drug extracts together with taurine, caffeine, and vitamins, and formulated based on the precepts of traditional Chinese medicine, was used. Male mice were forced to walk for 0-6 h at a speed of 3 m/min using a programmed motor-driven wheel cage. The serum and brain calcium levels in the mice were significantly increased following forced walking. The increase in brain calcium level began later and was more gradual than that in the serum calcium level, and reached its maximum value following forced walking for 3 h. The neostriatal dopamine level was also significantly increased, and locomotor activity significantly decreased following forced walking for 3 h. Prior oral administration of F-III (10 ml/kg) attenuated the increases in the serum and brain calcium levels, the increase in the brain dopamine levels, and the decrease in locomotor activity induced by forced walking. Taking into consideration these findings with our previous reports, it is suggested that physical fatigue leads to an increase in dopamine synthesis in the brain through a calcium/calmodulin-dependent system, thereby inducing behavioral changes, and that F-III inhibits this pathway and may alleviate overwork-induced physical fatigue.

Animals↗
PubMed2000

Production of the entire extracellular domain of BP180 (type XVII collagen) by baculovirus expression.

Bullous pemphigoid (BP) is an acquired autoimmune skin disease, and its target antigens are a 230 kDa plaque protein (BP230) and a 180 kDa transmembrane protein with interrupted collagenous domains (BP180, type XVII collagen), which localize at the hemidesmosome. In this study we have attempted to express the entire extracellular domain of BP180 (rBP180EC) as a secreted protein by baculovirus expression. Seventy out of 83 BP sera (84.4%) showed positive reactivity against rBP180EC by immunoblot analysis, and 56 out of 83 BP sera (67.5%) were positive against rBP180EC by ELISA. These figures were comparable with those when a bacterial recombinant protein encoding the NC16a domain of BP180 (rNC16a) was used as an antigen source. Reactivity of BP sera against rBP180EC by ELISA was completely abolished or significantly reduced by immunocompetition with rNC16a in 11 out of 14 BP sera tested, while the reactivity was not altered in the rest of the three sera. These findings indicate that the NC16a domain represents the major epitopes on the extracellular domain of BP180, although there are some other minor epitopes outside of NC16a which are uniquely expressed by rBP180EC. rBP180EC will be useful to develop a diagnostic tool for BP as well as to dissect a molecular role for BP180 in interactions of keratinocytes with epidermal basement membrane.

Autoantigens↗
PubMed2000

Fentanyl improves analgesia but prolongs the onset of axillary brachial plexus block by peripheral mechanism.

UNLABELLED: We evaluated the effects of fentanyl added to lidocaine for axillary brachial plexus block in 66 adult patients scheduled for elective hand and forearm surgery. In this double-blinded study, all patients received 40 mL of 1.5% lidocaine with 1:200,000 epinephrine, injected into the brachial plexus sheath using the axillary perivascular technique, and they were randomized into three groups. Group 1 was given lidocaine containing 2 mL of normal saline plus 2 mL of normal saline IV. Patients in Group 2 received lidocaine containing 100 microg fentanyl plus 2 mL of normal saline IV. Group 3 patients received lidocaine containing 2 mL of normal saline plus 100 microg fentanyl IV. Sensory and motor blockade were evaluated by using a pinprick technique and by measuring the gripping force, respectively. The success rate of sensory blockade for radial and musculocutaneous nerves and the duration of the sensory blockade significantly increased in Group 2 (323 +/- 96 min) as compared with Group 1 (250 +/- 79 min). However, onset time of analgesia was prolonged in every nerve distribution by adding fentanyl to brachial plexus block. IV fentanyl had no effect on the success rate, onset, or duration of blockade. We conclude that the addition of fentanyl to lidocaine causes an improved success rate of sensory blockade but a delayed onset of analgesia, although this may be accounted for by the decreased pH caused by the fentanyl. IMPLICATIONS: It is still unclear whether the addition of a peripheral opioid is useful for nerve blockade in humans. Peripheral application of fentanyl to lidocaine for axillary brachial plexus blockade in this study provided an improved success rate of sensory blockade and prolonged duration.

Analgesics, Opioid↗