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Biomedical subjects

A Ishihara

Publications and source records attributed to A Ishihara.

At least 181 records · Page 10Linked to original sources
PubMed1990

[Experimental studies in the healing process of the rats tongue after Nd:YAG contact laser irradiation. Scanning electron microscopic observation].

The Nd:YAG laser is useful in clinical oral surgery because of its superior hemostatic and coagulating effects. The purpose of this study was to examine the healing process of the tongue wounds caused by the Nd:YAG contact laser. A scanning electron microscope (SEM) was used, focusing mainly on the papillae filiformes of the tongue, and the results were compared with the pathological findings. The laser's effect on the microcirculatory network and the healing process were observed using the injection replica scanning electron microscope method. One hundred and eighty nine male Wistar rats were used in the experiment. Irradiation condition were 3, 6, 9 and 12-W for 1.0 second. The rats were sacrificed immediately after irradiation and on the 1st, 4th, 7th, 10th, 14th, 21st, 28th and 56th days after irradiation. The results were as follows. Pathological observations; Immediately after irradiation, the 3-W wound was observed below the lamina propria. The 6-W and 9-W wounds were observed from the upper musculi transversus linguae to the near center. The 12-W wound was observed to the center of the musculi transversus linguae. SEM observations; In the case of the 3-W wound, on the 7th day, normal epithelization was largely complete and there was a mucosal bulge which appeared to be regenerating papillae filiformes at the edge of the wound. On the 28th day, regenerated papillae filiformes were observed over the entire surface of the wound. The similar healing process was observed for the 6, 9 and 12-W wounds. However, in the cases of the 6-W and 9-W wounds the regenerated papillae filiformes were morphologically different from the original ones. In the case of the 12-W wound, on the 56th day regenerated papillae filiformes were observed around the edge of the wound but not in the center. Injection replica SEM observations; Concerning the effect of contact laser irradiation (6-W) on the tongue's microcirculatory network, the blood vessels at the edge of the wound were cut straight off, which suggested that they had been cauterized. Observations of the network during the healing of the wound showed that capillary loops had been restored and were related to the papillae filiformes.

Animals↗
PubMed1990

[T gamma lymphoma with CD3+ CD4- CD8- WT31- and TcR gamma delta].

An 18 years old female was admitted to hospital due to pancytopenia on May 25, 1987 and found to have petechiae, mild hepatomegaly and severe splenomegaly. The bone marrow was found to contain 12% of blast cells. Splenectomy was performed followed by CHOP therapy. In September, 1987 the peripheral blood was found to contain tumor cells, which turned out to be resistant to various combination chemotherapies. The patient died on August 21, 1988. The phenotype of tumor cells in this case was CD2+ CD7+ CD3+ CD4- CD8- WT31-. Genetic analysis detected rearrangement of the beta and gamma chain of TcR but not transcription or translation of the beta chain of TcR, while the antibodies of delta TCS 1 and TcR delta 1 to the delta chain of TcR were positive. From this fact, the present case was considered to be the malignant counterpart of normal CD3+ WT31- double negative T cells. The reactivity of this tumor cells to IL-2 and IL-1 beta suggested the association of the IL-2R beta chain.

Adolescent↗
PubMed1990

[Blood flow analysis in the left coronary artery in a patient with annulo-aortic-ectasia before and after Bentall's operation].

It has not been established that Bentall's operation induces beneficial effect on a coronary circulation in a patient with Annulo-Aortic-Ectasia. Availability of a small subselective coronary Doppler catheter makes it possible to study the effects of the operation on coronary circulation. In a 49 year old man with Annulo-Aortic-Ectasia, phasic coronary flow velocity in the left main truncus was measured using a 3F steerable Doppler catheter (DC-101, Millar Inc.) pre- and postoperatively with assessment of vasodilator reserve capacity of individual coronary arteries. After the operation, the velocity wave form in the LMT changed to a diastolic-predominant normal pattern with a relatively small systolic component. That is, Bentall's operation caused a marked reduction of systolic- to diastolic flow component ratio from 0.32 to 0.19. The postoperative coronary flow configuration in the LMT was characterized by the presence of predominant diastolic spike. It coincided with "Water hammer wave" in the aortic pressure tracings caused by sudden closing of mechanical valve leaflets. Preoperative intracoronary papaverine increased the ratio of peak to resting velocity (coronary flow reserve) to 2.0 times at the rest, and 3.0 times after the operation. These results suggest that Bentall's operation seems to induce beneficial effect on the myocardial coronary circulation.

Aortic Aneurysm↗
PubMed1990

[Endoscopic ultrasonography for assessing the horizontal spread of invasive gastric cancer].

The subjects were 64 cases of gastric cancer. In all 64 cases, resected specimens (formalin fixed) were subjected to endoscopic ultrasonographic examination by the water immersion method in order to assess the horizontal spread of the invasive gastric cancer. Ultrasonographic findings were compared with the histopathological findings of resected specimens. The tumor which invaded the submucosa or deeper layers was visualized as low echogenicity region in the third layer (corresponding to the submucosa) or deeper layers. The horizontal spread of the low echogenicity region represented that of the tumor or the associated fibrosis, but not the tumor itself. In the cases showing echo patterns which were characteristic of the peptic ulceration in the tumor focus (Type II-1, II-2, UL), the horizontal spread of cancer invasion in the submucosal layer or deeper layers (L Ca) was smaller than that of low echogenicity region depicted by ultrasonography (L U). In the other (Type II-3, III, A, B) cases, L Ca was almost comparable to L U.

Gastric Mucosa↗
PubMed1990

Suppression of cerebral evoked potentials preceding rapid reaction movement.

In this study we examined the gating of the cerebral evoked potentials during warning-imperative stimulus intervals and preceding the rapid movement. We also examined the possibility of the gating phenomenon occurring in the precentral cortex. The experiment showed that the amplitudes of cerebral evoked potentials increase at all C3 and CZ during the warning-imperative stimulus intervals. Therefore, it seems that gating does not occur within the central nervous system during warning-imperative stimulus intervals. Furthermore, we observed that preceding rapid movement, the amplitudes of the cerebral evoked potentials decreased at all C3 and CZ. In the present experiment, it does not seem that a peripheral mechanism plays a role in the rapid movement. Therefore, it can be concluded that the decrease in amplitude of the cerebral evoked potentials preceding rapid movement may be due to a central mechanism irrespective of afferent information. In addition, we confirmed that the amplitude of cerebral evoked potentials decreases considerably at the precentral cortex and that the attenuation in amplitude of cerebral evoked potentials is more pronounced over the CZ than over the C3.

Adult↗
PubMed1990

[Evaluation of combined resection of aortic wall in lung cancer invaded aorta].

Left pneumonectomy with combined resection of aortic wall was performed for three patients with lung cancer invaded aorta. In clinical and pathological examination, the following results were obtained. 1: In all three cases, metastasized subaortic lymphnodes invaded to medial wall of the descending aorta. 2: Microscopically, invasion of aortic wall was limited to the adventitia adjacent to the muscle layer. We think that the resection of whole layer of the aortic wall was preferable. 3: The resections of aortic wall were performed under partial clamp of aorta in one case, and under total clamp with the use of cardiopulmonary bypass in two cases. If the area of invasion is wide, total clamp was recommended. 4: Two patients died of recurrent disease 56 months and 20 months after surgery. In the other one, postoperative empyema was occurred. He died of bleeding from the suture line of Dacron patch to the aortic wall three months postoperatively. Covering of the bronchial stump and the patch of the aorta should be considered to prevent postoperative empyema.

Adenocarcinoma↗
PubMed1989

Menadione-linked alpha-glycerophosphate dehydrogenase activity of motoneurons in rat soleus and extensor digitorum longus neuron pools.

After injection of horseradish peroxidase into the soleus (slow twitch) and extensor digitorum longus (fast twitch) muscles, glycolytic enzyme activity as reflected by alpha-glycerophosphate dehydrogenase activity of labeled motoneurons in the neuron pool was examined. No differences were found in glycolytic enzyme activity of motoneurons between slow twitch and fast twitch neuron pools.

Animals↗
PubMed1989

Extracorporeal circulation influence on plasma atrial natriuretic peptide concentration in cardiac surgery patients.

An attempt was made to clarify the change of plasma human atrial natriuretic peptide (hANP) concentration before, during, and after cardiac surgery in heart failure with extracorporeal circulation. Plasma hANP concentration did not significantly decrease during total aortic cross clamping (ACC) with complete clamping of the superior and inferior vena cavae. This finding may be explained by the suppression of endopeptidase activities and the response of hANP receptors due to the low body temperature. Plasma hANP concentration strongly increased from 56.6 +/- 8.4 to 208.9 +/- 40.7 pg/ml (n = 5) by the release of total ACC. This strong increase of hANP in the plasma may occur due to the rapid increase of atrial pressure from zero to 12.5 mm Hg caused by releasing the total ACC. The molecular form of plasma hANP obtained after the release of total ACC was alpha-hANP alone, which was estimated by gel permeation chromatography and reverse HPLC.

Adult↗
PubMed1989

Histochemical profiles of fibers in the rat tibialis anterior muscle during early postnatal development.

The enzyme activities of intra- and extrafusal fibers in the tibialis anterior muscle of rats during postnatal development have been investigated. Muscle fibers 1 day after birth showed a uniform reaction for adenosine triphosphatase (ATPase), succinate dehydrogenase (SDH), and alpha-glycerophosphate dehydrogenase (alpha-GPD) activities. Fast-twitch (F) and slow-twitch (S) fibers with ATPase activity were found at 9 and 11 days. Thereafter, the type shift of muscle fibers from S to F was observed in the deep and middle portions. Fast-twitch oxidative glycolytic (FOG), fast-twitch glycolytic (FG), and slow-twitch oxidative (SO) fibers with ATPase, SDH, and alpha-GPD activities were found at 15 (the superficial portion) and 17 days (the deep and middle portions). The histochemical differentiation of intrafusal muscle fibers (7 and 9 days) was found earlier than that of extrafusal muscle fibers.

Adenosine Triphosphatases↗
PubMed1989

Cerebral motor potential preceding grip strength movement.

The relationship between the force of the movement and the motor potential (MP), and that between the degree of the muscular discharge and the MP were examined by the method of bipolar and monopolar derivation. The MP amplitudes were significantly higher at C3' and Cz than at other lead placements for right grip and higher at C4' and Cz for left grip. A significant difference was observed among all lead placements except at Cz-C4'. The MP amplitudes were significantly higher for a strong grip task than for a weak grip tasks. Moreover, the MP amplitudes were higher at higher degrees of muscular discharge. The MP usually occurred about 100 msec prior to the EMG discharge, as also confirmed by Deecke et al. Therefore, from the present results and other studies, we postulated that the MP may reflect the activity of the neurons in the motor and premotor cortices, which might contribute to movement initiation. In addition, the MP amplitudes measured using bipolar derivation were more explicit than those measured using monopolar derivation.

Adult↗
PubMed1989

Effect on the action potential of the low power Nd: YAG laser as irradiated directly to the nerve.

The present paper reports our studies of changes in the compound action potential after Nd: YAG laser irradiation of the rat's sciatic nerve. The nerve on one side was exposed and irradiated by Nd: YAG laser directly. The temperature of the irradiated nerve was also measured. 1) Under 100 mW irradiation the compound action potential and the temperature of the surface of the sciatic nerve did not show a detectable change. 2) Under 300 mW irradiation the compound action potential showed an increase in amplitude, and shortening in latency. A negative after-potential appeared within 30 secs of irradiation. The temperature on the sciatic nerve rose by 3 degrees C during the irradiation. 3) Under 500 mW irradiation the compound action potential decreased gradually in amplitude and ultimately disappeared. The temperature on the sciatic nerve reached more than 47 degrees C.

Action Potentials↗
PubMed1989

Structural analysis of phleboliths and salivary calculi.

Three phleboliths and ten salivary calculi in the submandibular duct were studied with scanning electron microscopy (SEM) and computer aided microanalyser (CMA). The surface of the phleboliths was rather even with some irregularity. According to their surface structure the salivary calculi were divided into three types: the rock-like type, the granular type, and the globular type. The phleboliths were classified into two types according to their cut surface: the calcified-core type, and the uncalcified-core type. The core structure was similar to the surface structure in the calcified-core type of phleboliths, but in the salivary calculi the core structure was different from the surface structure in that the cut surface of the core was an accumulation of circular or polygonal structures forming a honey-comb pattern which was surrounded by small projections distributed radially. On the basis of these results some etiological factors of phleboliths and salivary calculi are discussed.

Electron Probe Microanalysis↗
PubMed1989

Two cases of simple bone cyst suspected of being odontogenic tumors.

We report here two cases of simple bone cyst suspected of odontogenic tumors. The first case, a 17-year-old female, was introduced to our department by a dental practitioner because of a large radiographic defect of the bone. The patient had no subjective symptoms. The defect extended between 3 and the ascending ramus, and had multilocular radiolucency associated with bone expansion. The Marsupialization and curettage of the defect were performed. One year after the surgery, the defect was filled with new bone. The second case, a 14-year-old male, complained of occlusal pain in the anterior mandible. Irregular and unilocular radiolucency was seen radiographically in 4 + 2. The biopsy suggested an ossifying fibroma. Extirpation and curettage of the lesion were performed. Ten months after the surgery, the bone expansion disappeared.

Adolescent↗
PubMed1989

Neutral proteinases and inhibitors secreted by human rectal adenocarcinoma cell line (RCM-1).

A human rectal adenocarcinoma cell line, RCM-1, secreted some neutral proteinases: metallo-, serine and cysteine proteinases; and trypsin inhibitors into the serum-free conditioned medium (SFCM) in vitro. They were separated by anion-exchange and gel filtration high-performance liquid chromatography. SFCM from the cells of early passage numbers (20-24) contained native activities of serine proteinase and collagenolytic metalloproteinase. However, after several passages the native activities of them were diminished and latent form of metalloproteinase increased. In contrast to the native proteolytic activities, trypsin inhibitory activity was elevated in SFCM from the cells of passages 38-42. It inhibited the serine proteinase secreted by the same cells of early passage numbers. Furthermore, the serine proteinase was able to activate the latent form of metalloproteinase. Cooperative roles of these tumor-secreted proteinases and inhibitors may be important in tumor invasion.

Adenocarcinoma↗
PubMed1989

[A case of pulmonary mucormycosis accompanied by lymphocytic leukemia successfully treated by pulmonary lobectomy].

A 51 years old man with acute lymphocytic leukemia who was treated with antileukemic chemotherapy, developed sepsis and pneumonia. Secondary infection with Mucor intervened with abscess formation cured by lobectomy. The patient is doing well without evidence of recurrence, and treated successfully with anti-leukemic chemotherapy. Surgical treatment offers the last chance of survival in similar cases.

Humans↗
PubMed1989

Comparison among various movement tasks of cerebral motor potential preceding voluntary movement.

We examined the relationship between the movement potential (MP) and various movement tasks. We found that the MP amplitudes were the highest for the hand grip movement among various movement tasks. Furthermore, the present results indicated that a significant correlation was found between the MP latencies and prereaction time. The present experiments showed that there were changes in the latency and amplitude of the MP in rapid movements from a slightly sustained contraction and in fast reaction movements. Therefore, we noted that the MP amplitudes and latencies change corresponding to the type of movement tasks. Accordingly, it may be concluded that there is a close relationship between the MP and central motor output, namely physical factors (force and speed).

Action Potentials↗
PubMed1989

[A case report of tricuspid valve endocarditis due to Staphylococcus aureus with successful surgical treatment].

A 14-year-old boy had previously received right temporal lobectomy under the diagnosis of a malignant brain tumor. About one month after lobectomy, ventriculo-peritoneum shunt and ventriculo-atrium shunt were placed because hydrocephalus was progressed. The patient subsequently had a high fever probably due to wound infection of the shunt operation. Several blood cultures demonstrated Methicillin Resistant Staphylococcus Aureus (MRSA). Several sensitive antibiotics were administered for about 30 days, however these drugs were not effective. According to echocardiography, moderate tricuspid regurgitation and a large vegetation at the tricuspid valve were detected and isolated tricuspid valve endocarditis was diagnosed. Surgical intervention was necessary because of recurrent pulmonary emboli. After tricuspid valve replacement with a Björk-Shiley mechanical valve (31 mm), fever subsided and the patient was discharged on the 38th postoperative day. It is concluded that the surgical indications of the tricuspid valve endocarditis are as follows: 1. recurrent pulmonary emboli, 2. refractory right heart failure, 3. resistance against antibiotics.

Adolescent↗