Search PubMed⌕ Search

Biomedical subjects

T Ohyama

Publications and source records attributed to T Ohyama.

At least 217 records · Page 12Linked to original sources
PubMed1992

Aneurysm of the cervical internal carotid artery associated with Marfan's syndrome--case report.

An aneurysm of the internal carotid artery associated with Marfan's syndrome occurred in a 23-year-old female with a 2-year history of a pulsating lesion in the left neck, which progressively increased in size. Left carotid angiography demonstrated a giant saccular aneurysm at the origin of the internal carotid artery. The aneurysm was excised and end-to-end anastomosis performed without postoperative morbidity.

Adult↗
PubMed1992

Wear of denture teeth by use of metal plates. Part 3: Abrasive wear of posterior teeth and wear of opposing metal plates.

An in vitro evaluation of abrasive wear resistance of high-strength denture (HS) teeth and wear of metal plates (Pd alloy) on the opposing side was conducted. A total of 8 types of teeth were used in the experiments including 3 types of HS teeth, 3 types of conventional plastic denture (PL) teeth, porcelain teeth and metal teeth (Pd alloy). Sliding-induced wear tests were conducted by sliding these teeth over the metal plates. Abrasive wear resistance of the teeth was evaluated in terms of wear depth and weight loss. A comparison of wear depth showed that the abrasive wear resistance of HS teeth was 4.7 times that of PL teeth, 0.7 times that of porcelain teeth and 8.3 times that of metal teeth. Weight loss showed that the abrasive wear resistance of HS teeth was 3.3 times that of PL teeth, 0.2 times that of porcelain teeth and 11.4 times that of metal teeth. The weight loss of the metal plates was minimal when they slid over HS teeth, but increased in the order PL teeth, porcelain teeth and metal teeth.

Dental Alloys↗
PubMed1992

[Four cases of Hodgkin's disease treated with MOPP/ABV hybrid regimen using nitrogen mustard-N-oxide hydrochloride].

Four patients with fresh Hodgkin's disease were treated with MOPP/ABV hybrid regimen using nitrogen mustard-N-oxide hydrochloride (NH2-O). All patients responded well to this therapy and achieved complete remission. Toxicity was minimum except for an older patient. He was 70 years old and developed arrhythmia after MOPP therapy but recovered without any treatment. The continuation of therapy was possible by dose reduction in this case. We conclude MOPP/ABV regimen using NH2-O is valuable for the treatment of Hodgkin's disease.

Adult↗
PubMed1992

DNA conformation of the region preceding the beta-lactamase promoter of pUC19 which is required for efficient transcription.

The upstream region of the beta-lactamase promoter of Escherichia coli plasmid pUC19 has a DNA curvature (bent DNA). This region was replaced with another sequence by using randomly synthesized oligonucleotides. Among the reconstructed plasmids, a plasmid which could endow E. coli cells with the strongest resistance to ampicillin on plates was selected. Nucleotide sequence and DNA conformation of the altered region was investigated.

Base Sequence↗
PubMed1992

[Clinical studies on intravaginal administration of CDDP for dysplasia, carcinoma in situ and microinvasive carcinoma of the uterine cervix].

We attempted CDDP (cis-diaminedichloroplatinum) intravaginal administration by directly exposing the uterine cervix to CDDP in cases of dysplasia of the uterine cervix and cervical intraepithelial and micro-invasive carcinoma. Out of 12 patients, 7 had dysplasia of the uterine cervix (dysplasia was mild in 4, of an intermediate level in 1, 4 with mild dysplasia, 1 with and advanced in 2); 3 had carcinoma in situ, and 2 had microinvasive carcinoma. For CDDP intravaginal administration, a gauze tampon containing CDDP (5mg) was inserted into the vagina. CDDP administration was repeated daily for 10 days. The total dosage of CDDP administered was 50mg (new paragraph). During this period, vaginal cytologic examination was conducted and total plasma Pt content was determined daily for all. Following the completion of CDDP administration, the uterine cervices of those with dysplasia were histologically examined. For those with carcinoma in situ and microinvasive carcinoma, simple total hysterectomy was performed after intravaginal administration of CDDP to determine its therapeutic efficacy and the Pt concentration of the tissue; 1. In the 7 cases of dysplasia, dysplastic cell degeneration was observed 1-2 days after the start of intravaginal CDDP administration and these cells disappeared in all cases after its completion. 2. Sixteen histological sections of the resected cervical specimens from the 3 cases of carcinoma in situ showed complete disappearance of cancerous cells. 3. In the 2 cases of microinvasive carcinoma, no tumor cells were detected in one case; in the other case, tumor cells persisted in part of the resected specimen.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Intravaginal↗
PubMed1991

Numb chin syndrome secondary to Burkitt's cell acute leukemia.

We describe a case of Burkitt's cell acute lymphoblastic leukemia presenting with the bilateral numb chin syndrome as the initial symptom of the disease. Postmortem study of the trigeminal nerve showed heavy infiltrations of leukemic cells and destruction of axon and myelin by leukemic cells in the mandibular nerve.

Burkitt Lymphoma↗
PubMed1991

Vibration analysis of the human left ventricular posterobasal wall at the moment of the first heart sound emission.

We examined whether human left ventricular (LV) wall vibration at the first heart sound emission (LVvibr) could be a potential source of information about the left ventricular physical properties, as has been demonstrated by experimental forced vibration studies. LV posterobasal wall vibration in 51 subjects characterized by functional murmur (n = 13), mitral stenosis (n = 8), hypertrophic cardiomyopathy (HCM, n = 8), ischemic heart disease with old myocardial infarction (n = 12) and without prior infarction (n = 10), was detected with a miniature intraesophageal vibration sensor. Peak frequency, sharpness and peak power of LVvibr in patients with functional murmur and mitral stenosis were linearly related to the Q-vibration interval. HCM patients showed a higher peak frequency and sharper configuration in the power spectrum. However, differing from previous reports, we found no characteristic difference in configuration of power spectrum in patients with ischemic heart disease. These results suggest that human LVvibr possibly includes information demonstrated by experimental forced vibration analysis.

Adolescent↗
PubMed1991

[New method for estimating left ventricular myocardial elasticity by vibration analysis].

We solved numerical solutions of Advani-Lee's equation, which treats free vibrations of fluid-filled spherical shells, and forms the basis for non-invasive estimation of left ventricular myocardial elasticity. Numerical results showed that elasticity is approximated by E = 86.5.a2.f2 (E: elasticity (dyn/cm2), a: internal radius (cm), f: eigen-frequency (Hz)). To examine the accuracy of this theoretical equation in estimating elasticity, we made 7 spherical shells of silicone rubber, and compared the estimated elasticity by this equation with that by a standard stretch test. The elasticity calculated by Advani-Lee's equation and by stretch test proved to be nearly identical. Therefore, we concluded that we can estimate the elasticity of a spherical shell using this equation. We calculated the myocardial elasticity at the first heart sound emission in 25 normal persons with a simplified (approximated form of) Advani-Lee's equation. The mean elasticity in normal subjects was (7.04 +/- 2.46) x 10(5) dyn/cm2.

Elasticity↗
PubMed1991

Functional significance of the DNA curvature located near a promoter: an analysis using the beta-lactamase promoter of pUC19.

The upstream region of the beta-lactamase promoter of pUC19 has a DNA curvature. Whether the curvature plays some role in the transcription from the promoter or not has been studied. The overall three-dimensional structure of the region containing the promoter and the curvature seems to play some significant role in the transcription of the gene. Functional significance of the DNA curvature located in the vicinity of a promoter is discussed.

Base Sequence↗
PubMed1990

Morphological and physiological characterization of small multimodal ocellar interneurons in the American cockroach.

The morphology and physiology of small multimodal ocellar interneurons (SM-neurons) have been examined in the cockroach Periplaneta americana. The SM-neuron is monopolar with its cell body in the tritocerebrum near the esophagus. Its axon ascends to the protocerebrum and extends into the ocellar neuropil through the ocellar tract and the ocellar nerve. The axon sends a long collateral process towards the optic tract. The SM-neuron responded with spike discharges to various sensory stimuli. The collateral and many side branches along the axon in the deutocerebrum appear to be input regions from those sensory afferents. Cercal stimulation triggered most effectively a train of spikes in the SM-neuron: some of seven giant axons in the ventral nerve cord were involved in this pathway. Cercal stimulation also evoked depolarization in the large second order ocellar neurons (L-neurons). A possible neural connection between SM-neurons and L-neurons was examined pharmacologically. Interaction of ocellar illumination and cercal stimulation in the L-neuron was also examined. These data are discussed in relation to the ocellar function of cockroaches and in comparison with data obtained in other insects.

Animals↗
PubMed1990

Morphological and physiological characterization of descending ocellar interneurons in the American cockroach.

In the present study two types of descending ocellar neurons have been morphologically and physiologically identified in the cockroach Periplaneta americana: a descending ipsilateral ocellar neuron (DIO-neuron) and a descending contralateral ocellar neuron (DCO-neuron). Both DIO- and DCO-neurons possess a cell body near the ocellar tract in the protocerebrum and extend dendritic processes into the ipsilateral ocellar nerve. An axon of the DIO-neuron descends to the metathoracic ganglion, and its entire course is ipsilateral to the cell body. An axon of the DCO-neuron crosses the median plane of the protocerebrum and descends through the contralateral ventral nerve cord to the second abdominal ganglion. Both axons possess masses of branches in each ganglion as well as in the brain. Both DIO- and DCO-neurons showed no spontaneous spike discharges, and responded with a few off-spikes to ocellar illumination. They responded to various mechanical stimuli, like cercal stimulation with a train of spikes which was suppressed by ocellar illumination. Spikes of DCO-neurons caused postsynaptic potentials and spikes in some interganglionic metathoracic interneurons, and spikes in motor nerves. These data are discussed in relation to the ocellar function of the cockroach as well as in comparison with that of other insects.

Animals↗
PubMed1990

Left ventricular end-systolic stress-volume index ratio in aortic and mitral regurgitation with normal ejection fraction.

To evaluate the left ventricular contractile state in regurgitant valvular disease with normal ejection fraction, we analyzed the end-systolic stress-volume index relationship (ESSVR) by means of cineangiography in 15 normal subjects, 11 patients with aortic regurgitation (AR), and 10 patients with mitral regurgitation (MR) whose ejection fraction (EF) was 60% or more. The end-systolic stress-volume index ratio in normal subjects was 5.57 +/- 0.60 kdyne/cm5/m2 (mean +/- standard deviation), and we defined the range including +/- 2 standard deviations of the ratio as the normal ESSVR range. Six patients with AR and five patients with MR placed inside the normal ESSVR range, termed AR IN and MR IN, but the remaining five patients with AR and MR placed to the right of the normal range, termed AR OUT and MR OUT. EF did not differ between patients with AR IN and AR OUT (69.4 +/- 5.4 verus 70.7 +/- 6.1%) and between MR IN and MR OUT (71.6 +/- 3.6 versus 71.1 +/- 7.9%). The EF of the subdivided groups with AR and MR also did not differ from that of normal subjects (70.7 +/- 7.3%). This finding showed that the left ventricular contractile state was depressed in patients with AR OUT and MR OUT despite a normal EF. In AR and MR the end-systolic stress and end-systolic volume index of OUT did not differ from those of IN, but the end-diastolic volume index of OUT was larger than that of IN (AR OUT 156.8 +/- 27.9 versus AR IN 110.8 +/- 24.1 ml/m2, MR OUT 160.5 +/- 44.7 versus MR IN 101.0 +/ 16.6 ml/m2; both p less than 0.05), and the regurgitant fraction of OUT was higher than that of IN (AR OUT 52.6 +/- 13.6 versus AR IN 29.7 +/- 13.3%, MR OUT 52.9 +/- 10.2 versus MR IN 30.2 +/- 11.4%; both p less than 0.05). In addition, there was a linear inverse correlation between the end-systolic stress-volume index ratio and the end-diastolic volume index in all subjects (r = -0.82, n = 36). In normal subjects there was a linear inverse correlation between end-systolic stress and the EF (r = -0.91, n = 15), but this relationship failed to separate patients with OUT from those with IN. Results of the present study suggest that some patients with AR and MR whose EF was normal had a depressed contractile state, and these patients had a large end-diastolic volume index and a high regurgitant fraction.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1990

Easy dissection of hard and thickened pericardium on constrictive pericarditis.

The keys to successful pericardiectomy for constrictive pericarditis are early operation and as complete a pericardiectomy as possible. With the high-speed burr it is easy and safe to dissect the calcified pericardium and define the epicardium even in a small operative field such as the inferior or posterior portion of the heart. This method has the important ability to perform very complete pericardiectomy.

Adult↗
PubMed1990

Brain abscess associated with congenital pulmonary arteriovenous fistula.

A case of brain abscess associated with congenital pulmonary arteriovenous fistula was presented and 52 reported cases were reviewed. The brain abscess was successfully treated with repeated aspiration and drainage, and the pulmonary arteriovenous fistula, located in the right lower lobe, was resected. The arteriovenous fistula occurs as a common pulmonary manifestation of hereditary hemorrhagic telangiectasia; however, no symptoms suggesting these two were noted in this case. Brain abscesses can be an initial clinical manifestation in asymptomatic pulmonary arteriovenous fistula. This possible association should be borne in mind in cases of brain abscesses of unexplained etiology.

Arteriovenous Fistula↗
PubMed1990

Immunoblot analysis of serum IgG, IgA and IgE responses against larval excretory-secretory antigens of Anisakis simplex in patients with gastric anisakiasis.

To increase our understanding of the immune response to Anisakis infection, antigen specific IgG, IgA and IgE responses were identified using an immunoblot technique after polyacrylamide gel electrophoresis of excretory-secretory products from the larval stage of Anisakis simplex. Nine sera were drawn from proven cases of gastric anisakiasis within 3 days after symptoms had developed. The molecular weight of the major antigenic bands were distributed between 50 kDa and 120 kDa of the antigens. In nine cases of gastric anisakiasis, three of them were positive for IgG response, five for IgE, and six for IgA, respectively. None of control sera recognized the antigenic bands in IgA and IgE responses. In contrast, two controls had IgG antibodies against 1-2 proteins in the 65-95 kDa region. The antigenicity of the excretory-secretory products was lost following treatment by 0.2% trypsin, but not by 0.2 M periodic acid. Based on the results of reactivity to lectins, antigenic bands of the ES products possessed mucin type glycoconjugate residues in their protein portion. This indicates that the humoral responses of IgA and IgE antibodies to the larval ES antigens are a more reliable index of infection than that of the IgG response.

Adult↗