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Masanobu Tanaka

Publications and source records attributed to Masanobu Tanaka.

12 recordsLinked to original sources
PubMed2005

Sonochemical decomposition of perfluorooctane sulfonate and perfluorooctanoic acid.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are shown to be globally distributed, environmentally persistent, and bioaccumulative. Although the toxicities of these compounds were reported, the cleanup procedure from the environment is not developed because of their inertness. In this report the sonochemical degradations of PFOS and PFOA to the products through the fission of the perfluorocarbon chains were observed and the half-life times of the PFOS and PFOA degradations under an argon atmosphere determined to be 43 and 22 min, respectively. The shortening of perfluorocarbon chain of PFOS and PFOA leads to the lowering of the toxicity in view of the decrease of the persistence, and the technique would contribute to the remediation of the environmental pollution by these compounds.

Alkanesulfonic Acids↗
PubMed2005

[Incongruous homonymous quadrantanopia due to suprasellar calcificated lesions].

A 53 year-old woman with a history of tuberculous meningitis at 3 years of age incidentally found a right incongruous homonymous quadrantanopia in ophthalmologic check-up. On magnetic resonance imaging and helical computed tomography, the left optic tract was obscured by suprasellar calcified lesions. The left internal carotid artery was diffusely narrowed and occluded at its terminal portion as demonstrated by cerebral angiography. The calcificated lesions were diagnosed to derive from old tuberculous meningitis on the basis of her history, their location and the association of vascular occlusive changes. Incongruous homonymous hemianopsia due to optic tract damage is usually caused by tumor or aneurysm. Its occurrence by calcified inflammatory lesions has never been reported previously. The present case is considered of value in this respect.

Calcinosis↗
PubMed2004

Pain in arthroscopic knee surgery under local anesthesia.

BACKGROUND: We evaluated pain during arthroscopic knee surgery performed under local anesthesia, with respect to various types of lesions and specific procedures used. PATIENTS AND METHODS: Arthroscopic surgery was performed on 63 joints (61 patients), with a median age of 49 years. We asked the patients to describe the pain experienced at each step of the procedure, and to compare the level of pain experienced at the time of injection and during the operation, using a visual analog scale (VAS). RESULTS: Pain experienced at the time of injection of the local anesthetic was more severe than the pain experienced during the surgical procedure. Local anesthesia provided good pain control during partial resection of the meniscus, chondroplasty, and removal of free bodies. Patients sometimes experienced more pain during treatment of the suprapatellar pouch, including the plica and the anterior cruciate ligament. INTERPRETATION: Injection of the local anesthetic was usually the most painful phase of the entire procedure. Patients were generally satisfied with the pain control.

Adolescent↗
PubMed2003

Tetrahedranyllithium: synthesis, characterization, and reactivity.

The first representative of stable tetrahedranyl anion, tris(trimethylsilyl)tetrahedranyllithium (3), has been synthesized by the reaction of tetrakis(trimethylsilyl)tetrahedrane (2) with methyllithium in tetrahydrofuran. The structural characterization of the tetrahedranyllithium has been achieved by X-ray crystallography, showing that the structure of 3.(TMEDA)1.5 represents a stretched tetrahedron. The endocyclic C(Li)-C(SiMe3) bond lengths range from 1.5408(15) to 1.5441(15) A (av 1.5425(15) A), and are longer than the endocyclic C(SiMe3)-C(SiMe3) bond lengths, which range from 1.4961(15) to 1.5009(15) A (av 1.4986(15) A). Methyl- and hydrogen-substituted tetrahedranes have also been prepared by the reaction of 3 with dimethyl sulfate and cyclopentadiene, respectively.

Journal Article↗
PubMed2003

Simultaneous live video presentation during knee arthroscopy.

To improve patient understanding, we evaluated prospectively the effect of patient-observed simultaneous surgeon-explained live video during knee arthroscopy. Patient satisfaction, understanding, and tolerance of the tenderness and pain were measured by a questionnaire completed immediately after the procedure. There were 72 patients (41 men, 31 women) with a mean age of 47 years; 76 joints were treated among them. All but one were comfortably able to watch the live video of the procedure, and 89% of the patients reported a good understanding of and satisfaction with the procedure. Moreover, if the patients ever had to have another arthroscopy, 66% answered that they "certainly" wanted a live video presentation, and 25% "somewhat" desired it. Live video-presented outpatient arthroscopic knee surgery could be considered a method for improving patient understanding of knee pathology.

Adolescent↗
PubMed2002

Tetrakis(trimethylsilyl)tetrahedrane.

Tetrakis(trimethylsilyl)tetrahedrane 3 has been synthesized upon irradiation of tetrakis(trimethylsilyl)cyclobutadiene 8, which can be prepared either by thermal nitrogen elimination from trimethylsilyl[1,2,3-tris(trimethylsilyl)-2-cycloprop-1-enyl]diazomethane 7 or by mild oxidation of cyclobutadiene dianion 9 with 1,2-dibromoethane. The structural characterization of tetrahedrane 3 has been achieved by X-ray crystallography. The surprising thermal stability of 3 - which is stable up to 300 degrees C - is discussed.

Journal Article↗
PubMed2002

Simultaneous determination of metabolites of trimethylbenzenes, dimethylbenzylmercapturicacid and dimethylhippuric acid, in human urine by solid-phase extraction followed by liquid chromatography tandem mass spectrometry.

We describe a novel method for the determination of three kinds of dimethylbenzylmercapturic acids (DMM) and six kinds of dimethylhippuric acids (DMH), found in urine as metabolites of trimethylbenzenes, based on liquid chromatography/electrospray ionization tandem mass spectrometry. A solid-phase extraction procedure was used for the extractions of DMM and DMH from a urine sample, and the separation was performed on a reversed-phase C(30) column. The analytes were ionized by electrospray in the positive-ion mode. Operating in the multiple reaction monitoring mode, the linearity of the relative mass spectrometric responses to the internal standard versus analyte concentrations were established in the range 0.1-100 ng ml(-1). The extraction procedure was rapid and the relative standard deviations were below 5%. The detection limits of DMM and DMH in the urine by the proposed method were in the ranges 0.26-0.41 and 0.42-2.0 ng l(-1), respectively. Furthermore, DMM and DMH were detected in a urine sample from an individual who did not suffer from occupational exposure to trimethylbenzenes, by using this method.

Acetylcysteine↗
PubMed2002

Establishment of the T-cell large granular lymphocyte leukemia cell line MOTN-1 carrying natural killer-cell antigens.

A novel interleukin-2 (IL-2) dependent leukemia cell line MOTN-1 was established from the peripheral blood of a 63-year-old woman with T-cell large granular lymphocyte (LGL) leukemia in chronic phase. Primary peripheral blood leukemia cells were CD3+, CD5+, CD7+, CD56+, CD94+, CD161+, TcRalphabeta+, and HLA-DR+. The immunoprofile of the established cell line MOTN-1, however, showed CD3-, CD5-, CD7+, CD56+, CD94+, CD159+, CD161+, TcRalphabeta- and HLA-DR+; the MOTN-1 cells were cytoplasmatically positive for CD3varepsilon and the products of the T-cell receptor (TcR) genes beta and gamma. While the TcRbeta and TcRgamma genes were rearranged, the TcRdelta gene was found to be deleted. DNA fingerprinting and chromosome analysis identifying the t(2;6)(q?23;q?21) and t(12;18)(q13;q?22) alterations demonstrated the authenticity and the malignant nature of the cell line. The scientific significance of MOTN-1 lies in (1) the rarity of this type of leukemia cell lines, (2) the co-expression of various T- and natural killer (NK)-cell-associated markers, and (3) its unique chromosomal aberrations.

Antigens, CD↗
PubMed2002

Mechanoreceptors and length of the patellar ligament after Ho-YAG laser treatment: a long-term follow-up in rabbits.

We studied the shortening and the number of mechanoreceptors in the patellar ligament up to 18 months after Ho-YAG irradiation of the ligament's surface in 35 rabbits. The ligaments shortened an average 13% immediately after irradiation. After treatment, we divided the rabbits into a mobilized or immobilized group. At 2 weeks and 12 months after treatment both groups showed no shortening of the ligament, as compared to the intact ligament while that in the mobilized group had elongated at 12 months. Fewer Pacinian and Ruffini corpuscles were found in the irradiated ligaments than in the intact ones at 2 weeks after treatment, but we found no difference between irradiated and intact ligaments at 18 months after treatment.

Animals↗