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Biomedical subjects

Y Iwata

Publications and source records attributed to Y Iwata.

At least 199 records · Page 11Linked to original sources
PubMed1987

[A human case of pulmonary dirofilariasis suspected to be lung cancer].

A 50-year-old man in Kitakyushu City visited a hospital for evaluation of an opacity in a routine chest X-ray film. After examinations by bronchoscopy and chest roentgenography, a clear coin lesion was found in the middle lobe of the right lung and was suspected to be a lung cancer. A right thoracotomy was performed to remove it. The lesion (10.6 X 9.8 mm) was a well-defined ellipsoid granuloma due to a foreign body with a central zone of necrosis surrounded entirely by a fibrous wall. In a cross section of the dissected granuloma two degenerated worm-like structures were revealed. The sections of the worm (216-240 X 296 mu m at the greatest diameter) had at least a 3-layered cuticle and prominent internal longitudinal cuticular ridges but no external cuticular ridges. The lateral chords were as high as the muscle layer which consisted of abundant somatic muscle (more than 30 muscle cells/quadrant). Judging from these morphological characteristics, the pulmonary granulomatosis was diagnosed to be due to an immature dog heartworm, Dirofilaria immitis. This identification was further supported by results from immunological methods. The present case is the 56th human case of dirofilariasis (the 39th as a pulmonary case only) in Japan.

Diagnostic Errors↗
PubMed1987

Surgical treatment of hypertensive intracerebral haematoma by CT-guided stereotactic surgery.

Ninety consecutive cases of hypertensive intracerebral haematoma were treated with CT guided stereotactic evacuation. The patients were composed of 61 males and 29 females, ranging from 42 to 87 years old. The location of haematoma was either in the putamen (59 cases) or in the thalamus (31 cases). The average volume of the evacuated haematoma was 21.4 ml in the putaminal haematoma and 14.0 ml in the thalamic haematoma. Postoperative follow-up study in 46 patients showed good recovery of neurological deficits both in putaminal and thalamic group. Criteria of surgical indication of CT-guided stereotactic evaluation of intracerebral haematoma were advocated based on the author's clinical experience.

Adult↗
PubMed1987

Short latency somatosensory-evoked potentials--direct recording from the human midbrain and thalamus.

Short latency somatosensory-evoked potentials were recorded from the human thalamus and the midbrain during stereotactic operations. Several subcomponents were recognized on the peak of N18. These were recorded with maximal amplitude at the border between the caudal portion of the thalamus and the rostral midbrain. Two positive-negative responses, not previously shown, were observed between P14 and N18. These responses were prominent in the rostral midbrain. These findings indicate that the ascending phase of N18, and the N18 itself, are the compound potential generated in the mesodiencephalic junction.

Brain Mapping↗
PubMed1987

Three-contrasts method: an ultrasound technique for monitoring transcervical operations.

The "three-contrasts method" of ultrasonography is designed to monitor transcervical operations for submucous uterine myomas and uterine septa when a pediatric urologic resectoscope is used. This monitoring method has proved more effective than concomitant laparoscopy. The pediatric resectoscope can also be used efficiently for diagnostic and therapeutic purposes without dilating the cervical canal.

Endoscopes↗
PubMed1987

[The development of a new flexible hysterofiberscope and its clinical application].

Hysteroscopy is a diagnostic method for intrauterine lesion. Most kinds of hysteroscope are rigid in type. Cervical dilatation and insertion of the trocar are necessary for hysteroscopy. These procedures can be very painful to the patient. Also subsequent blood clotting and injury to the endometrium may interfere with the diagnosis. With the help of Fuji Photo Optical Company, a new flexible hysterofiberscope (3.7 mm in diameter) was developed. The scope is divided into three portions; a front flexible part, a rigid middle part and a soft rear part. Cervical dilatation and anesthesia were not required even in a primiparous woman. The operator can observe the cervical canal, the uterine cavity and the tubal ostium very easily in a comfortable position. From Nov. 85 to Sep. 86 we carried out hysteroscopy in 411 patients with this new scope. The fluid medium which we used was a solution of 10% dextrose in water. The indications for hysteroscopy were abnormal uterine bleeding (187 cases), uterine myoma (80 cases), sterility (52 cases), post-transcervical surgery (22 cases) and others (70 cases). No complications were encountered during or after the procedure. The results were satisfactory. This new flexible hysterofiberscope has been proved an efficient tool for intrauterine diagnosis.

Endoscopes↗
PubMed1987

[CT-guided stereotactic brachytherapy in deep-seated malignant gliomas--interstitial irradiation by double-catheter after-loading method].

CT-guided stereotactic brachytherapy has been performed for the deep-seated malignant gliomas using the double-catheter after-loading method. The catheter system consists of two coaxial polyethylene tubes with closed tips. The outer catheter is 3.0 mm in outer diameter and 2.4 mm in inner diameter. The inner catheter is 2.0 mm in outside diameter and 1.4 mm in inside diameter, and contains the radioactive sources. Localization of the target volume is determined by the preoperative findings of computed tomography (CT), magnetic resonance imaging (MRI), and cerebral angiography. Dosimetry and dose planning are so finalized for the target volume as to be irradiated interstitially more than tumoricidal dose. After stereotactic biopsy of the deep-seated brain tumors, stereotactic implantation of the outer catheters is performed using Iseki Stereotactic System in the CT room. Burr holes had been previously opened in the operating room. The inner catheters containing nonradioactive sources (dummy sources) are inserted, and skull X-p is taken to confirm the position of the dummy sources, and to calculate the dosimetry by computer. The inner catheters are replaced with catheters containing radioactive sources (226Ra) in the irradiation room. 226Ra sources deliver at least 500 rads/day (approximately 20 rads/hr) to the target volume as interstitial irradiation. Two patients of malignant gliomas treated with this procedure were shown as representative cases. These patients underwent CT-guided stereotactic brachytherapy as "boost" combined with conventional external irradiation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1987

[EEG topographic changes of brain abscesses in children].

EEG topography was investigated before and after surgical treatment in 4 patients with brain abscess aged from 5 to 13 years. According to the recording technique designed by Matsuoka and Ueno, the recorded EEG for each 5 seconds was analyzed to obtain square roots of power spectra for each band of delta (2-3.8 Hz), theta (4-7.8 Hz) and alpha (8-12.8 Hz) which were then added for the 60-seconds duration of each trial. After that, numerical matrix presenting the topographic distribution of spectral energy of each band were constructed and displayed as color images. In addition, the EEG topographies of brain abscesses were compared with the CT scans simultaneously obtained. In all of four cases before surgical treatment of the brain abscess, the location of the focal delta wave on the EEG topography was more closely related to the site of brain abscess comparing with its correlation between the location of the delta focus on the conventional EEG and the site of brain abscess. In contrast, as for the theta wave, there was no prominent correlation to the site of the brain abscess. In the early stage of 10-15 days after aspiration of the brain abscess, the most characteristic change of the EEG topography was an approximately 25% reduction of the maximum equivalent voltage of delta band with associated disappearance of the sharply located focal delta wave being noted before aspiration.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

[Agenesis of the left internal carotid artery with an ophthalmic artery arising from the posterior communicating artery].

A case of agenesis of left internal carotid artery is reported. The patient is a forty one-year-old house-wife with sudden episode of headache when she had a fever. CT scan of the head showed a small high density area in the right frontotemporal subcortical region. Four vessel cerebral angiography demonstrated negative lesion except for complete absence of the left internal carotid artery. The blood supply to the left cerebral hemisphere was provided both through the tortuous anterior communicating artery and through the enlarged left posterior communicating artery. Left ophthalmic artery arose from the left posterior communicating artery. The embryological developmental process of this kind of vascular anomaly as well as the relationship between intravascular hemodynamic stress and the induction of cerebral aneurysm were discussed in detail.

Adult↗
PubMed1986

Inhibition of reverse transcriptase activity by 2',3'-dideoxythymidine 5'-triphosphate and its derivatives modified on the 3' position.

Inhibitory effects of 2',3'-dideoxythymidine 5'-triphosphate (ddTTP) and its three derivatives modified on the 3' position of ribose moiety [3'-azido-2',3'-dideoxythymidine 5'-triphosphate (3'-N3-ddTTP), 3'-amino-2',3'-dideoxythymidine 5'-triphosphate (3'-NH2-ddTTP) and 2'-deoxyxylo-furanosylthymine 5'-triphosphate (dXTP)] on the activity of the reverse transcriptase purified from Rauscher murine leukemia virus were examined and compared with each other. When (rA)n X (dT)12-18 was used as the template X primer in the presence of manganese ion, all these compounds except 3'-NH2-ddTTP inhibited the reverse transcriptase activity in competitive fashion with respect to the dTTP substrate. The inhibition potentials of these compounds are ordered as follows: 3'-N3-ddTTP (Ki = 1.8 microM) greater than ddTTP (Ki = 9.3 microM) greater than dXTP (Ki = 16.3 microM), and the Ki values of these inhibitors are smaller than the Km of dTTP (30 microM). The observed inhibitions were mainly due to competition between the dTTP substrate and inhibitor rather than chain-termination of the elongating DNAs caused by incorporation of these dideoxy compounds.

Binding, Competitive↗
PubMed1986

Histopathological changes, mucin production and cellular DNA content in rectal mucosa of patients with ulcerative colitis: a comparison between findings in adults and adolescents.

Histopathological examination, specific mucin staining and analysis of cellular DNA content of rectal mucosa were carried out in twenty-eight tissue specimens biopsied from ten adult and eight adolescent patients with ulcerative colitis. There was an increase in proliferative activity in the rectal mucosa in both groups with active colitis, but, there were no significant differences in the potential for malignant transformation of rectal mucosa in these groups.

Adolescent↗
PubMed1986

Effects of immunostimulation with OK432, coenzyme Q10, or levamisole on dimethylhydrazine-induced colonic carcinogenesis in rats.

Effects of immunostimulation with OK432, Coenzyme Q10 (Co-Q10), or levamisole on dimethylhydrazine (DMH)-induced colonic carcinogenesis were investigated in 45 Donryu-rats. The manipulation with one of these immunopotentiators did not prevent DMH-induced colonic carcinogenesis in these rats. However, the number of tumors was significantly reduced and the incidence of invasive carcinomas decreased by immunostimulation. The treatment also reduced the number of lesions with epithelial dysplasia within the flat colonic mucosa.

1,2-Dimethylhydrazine↗
PubMed1986

Squamous cell carcinoma of the urachus. A case report and review of literature.

A rare case of squamous cell carcinoma (SCC) is reported. A cystic tumor, measuring 4 X 4 cm was surgically removed from the supravesical portion in a 77-year-old woman. Macroscopically, it had a communicating canal to the urinary bladder. Microscopically, well differentiated squamous cell carcinoma with pearl formation was noted. An aspiration biopsy was helpful for the histopathological diagnosis at operation. The patient developed purulent peritonitis because of rupture of the tumor which was vulnerable to infection. Six documented cases and the present case were reviewed. The tumors were classified into two types on morphological features: supravesical type and intramural type. Site and local extension of the tumor accounted for clinical features of each type. The authors considered that SCC cells were derived from totipotential epithelial lining of the urachal remnant.

Abdominal Neoplasms↗
PubMed1986

Long-term follow-up study of rostral mesencephalic reticulotomy for pain relief--report of 34 cases.

A long-term follow-up study of rostral mesencephalic reticulotomy (RMR) for pain relief is presented. 34 patients (24 males and 10 females) were operated. Ages ranged from 18 to 65 years. The follow-up period was 1-70 months. The overall effectiveness of RMR showed good relief of pain in 23 patients (67%). The study of effectiveness of RMR according to type of pain showed good relief of pain in 5 out of 6 patients (83%) with nondenervation pain, whereas satisfactory pain relief was obtained in 18 out of 28 patients (64%) with denervation pain.

Adolescent↗