PubMed Health⌕ Search

Biomedical subjects

S Baba

Publications and source records attributed to S Baba.

At least 325 records · Page 18Linked to original sources
PubMed1996

Voluntary suppression of caloric nystagmus under fixation of imaginary or after-image target.

Voluntary suppression of caloric nystagmus was investigated in 10 normal subjects under the following three conditions; i) with visible, earth-fixed target in the dark ("visual"), ii) with imaginary target in the dark ("imaginary"), and iii) an after-image on the fovea in the dark ("after-image") Subjects were able to suppress caloric nystagmus with a visible target very well, but they could only partially suppress caloric nystagmus with imaginary target and with after-image. The degree of suppression in the "imaginary" and "after-image" conditions was significantly less than that in "visual", but was not zero. These results are consistent with those of many reports about visual-vestibular interaction and VOR voluntary modification during rotation, and suggest that smooth pursuit eye movements (SPEM) system plays a major role in visual suppression during caloric nystagmus.

Adult↗
PubMed1996

Non-visually induced smooth pursuit eye movements using sinusoidal target motion.

Non-visually induced smooth pursuit eye movements (SPEM) were assessed in 8 healthy subjects. Targets were the subjects finger tip movements as somatosensory stimulus and a moving sound source as acoustic stimulus. Horizontal sinusoidal target movements were provided at an amplitude of 15 degrees and frequencies of 0.2, 0.4 and 0.8 Hz. In comparison with conventional visually-induced SPEM, low gain and phase lead were observed, particularly at higher frequency target movements. There was considerable inter-individual variability in the non-visual SPEM performance. A positive correlation between the gains of somatosensory and acoustic SPEM was observed in each subject. We suggest a common SPEM generator, including predictive control for the non-visual SPEM and to some extent for the visual SPEM.

Acoustic Stimulation↗
PubMed1996

Influence of foveal afterimage on non-visually induced pursuit eye movements.

Smooth pursuit eye movements (SPEMs) were measured during trials with an acoustic target, a somatosensory target (finger tip), and an imaginary target. Under these non-visual conditions the induced SPEMs were investigated both with and without a foveal afterimage. Ten normal subjects were examined. Considerable inter-individual differences were observed in performance of the non-visual SPEMs. However, the presence of an afterimage did not influence SPEMs during acoustic or somatosensory pursuit. It is concluded that the capacity for "visualization" may not involve the ability for non-visual SPEMs. As in imaginary target condition the subjects could not elicit SPEM without the afterimage, clearly the memory of target motion alone cannot generate SPEMs. The afterimage may help the subject to convert the memory of target motion into the perception of virtual target motion.

Acoustic Stimulation↗
PubMed1996

Influence of superimposed optokinetic stimulus on smooth pursuit eye movements elicited by sinusoidal spot target oscillation.

In 6 healthy subjects, smooth pursuit eye movements (SPEMs), elicited by sinusoidal spot target oscillation, were measured against three different backgrounds: dark, stationary texture (texture), and texture background movement in-phase with the spot target (coupled). Spot-target oscillation frequencies ranging between 0.2 to 1.6 Hz and peak velocities ranging between 19 to 75 degrees/s were employed. SPEM gain did not differ significantly among the three backgrounds below 0.8 Hz. However when at 1.6 Hz it responded to a peak velocity of 75 degrees/s, the gain for the "coupled" background condition was greater than that for the "dark" condition, which in turn was greater than the gain for "texture". However, SPEM phase delays were found to be similar for the three background conditions. Since the responses during "coupled" and "texture" backgrounds are most likely elicited by rapid-rise optokinetic reflex (OKR) interaction it can be concluded that SPEMs and the rapid-rise OKR system have the same latency (response) time.

Adult↗
PubMed1996

[A case report of Takayasu's arteritis with aortic pseudoaneurysm caused by aortic perforation].

A 47-year-old man presented with hemoptysis. From around June 20, 1995, he had symptoms of a common cold, but hemoptysis suddenly occurred on July 1 and he was brought to hospital. The chest X-ray film showed pleural effusion and enlargement of the mediastinum. CT scans showed calcification of the aorta, with a pseudoaneurysm 8 cm in diameter anterior to the descending aorta. When thoracotomy was performed under partial extracorporeal circulation, the thoracic cavity was found to be filled with bloody hydrothorax and hematoma, and the lower lobe of the left lung was adherent to the descending aorta. After a longitudinal incision was made in the aorta, a perforation 7 mm in diameter was identified in the posterior wall, and this was assumed to be the cause of the pseudoaneurysm. This part of the aorta was replaced with a Woven Dacron graft. Takayasu's arteritis was diagnosed by histological examination of the resected specimen, and the changes in the aortic wall at the site of perforation were considered to be chronic. About 30% of patients with this disease have aortic ectasia, but only a few pseudoaneurysms have been reported. Since the pseudoaneurysm occurred in our patient after reduction in the dose of medication, the development of perforation was suggested to be related to this change. In the future, this patient will require careful follow up for anastomotic aneurysm.

Aneurysm, False↗
PubMed1996

Sleep apnea associated with congenital diseases and moderate hypertrophy of tonsils.

In this paper, we studied 3 children with moderate hypertrophy of the palatine tonsils and adenoids and serious congenital diseases. The first patient was a 4-year-old girl with Fallot's tetralogy, the second was a 6-year-old girl with Goldenhar syndrome and ventricular septal defect, aortic stenosis and patent ductus arteriosus, and the third was a 3-year-old boy with cerebral palsy and epilepsy. We examined obstructive apnea during sleep in these patients using all-night polysomnogram or apnomonitor before surgical therapy. After tonsillectomy or adeno-tonsillectomy we confirmed significant improvement of clinical symptoms and obstructive sleep apnea in these patients by all-night polysomnograms or apnomonitor.

Adenoids↗
PubMed1995

Tumor necrosis factor and coagulopathy in patients with prostate cancer.

This study was undertaken to evaluate the relationship between serum tumor necrosis factor (TNF) and coagulopathy in patients with prostate cancer. TNF levels in 104 sera obtained from 101 prostate cancer patients were determined using an enzyme immunoassay. Serum levels of fibrin/fibrinogen degradation product E fragment (FDP) and plasma levels of fibrin degradation product D-dimer in patients with elevated serum TNF levels were 1221.95 +/- 375.94 ng/ml and 27.34 +/- 9.81 micrograms/ml, which were significantly higher than those (FDP, 94.35 +/- 13.17 ng/ml; D-dimer, 1.03 +/- 0.20 micrograms/ml) in patients with undetectable serum TNF levels (P < 0.01). In addition, patients with elevated serum TNF levels showed significant increases in plasma levels of thrombin-antithrombin-III complex and plasmin-alpha 2-antiplasmin inhibitor complex and a significantly higher incidence of positive plasma soluble fibrin monomer complex than did those with undetectable serum TNF levels. The percentage of prothrombin time was significantly decreased in the group with elevated serum levels of TNF. Serum levels of TNF were significantly elevated in patients with serum FDP levels of > or = 200 ng/ml than in those with serum FDP levels of < 200 ng/ml (3.91 +/- 0.45 versus 2.17 +/- 0.08 units/ml) and in patients with plasma D-dimer levels of > or = 2 micrograms/ml than in those with plasma D-dimer levels of < 2 micrograms/ml (3.82 +/- 0.48 versus 2.10 +/- 0.06 units/ml). These results suggest that TNF may be one of the pathogenetic factors that could explain the occurrence of coagulopathy in patients with prostate cancer.

Adenocarcinoma↗
PubMed1995

Comparison of the inhibitory effect of the angiogenesis inhibitor, TNP-470, and mitomycin C on the growth and liver metastasis of human colon cancer.

Angiogenesis inhibitors have attracted considerable interest. The anti-tumor and anti-metastatic effects of TNP-470, an angiogenesis inhibitor, and mitomycin C (MMC), a representative anti-neoplastic agent, were investigated using a xenotransplanted human colon cancer, TK-4. Suturing of small pieces of TK-4 tumors to the cecal wall in nude mice (orthotopic transplantation) induced liver metastasis. Mice were randomly divided into 3 groups; a control group given saline solution, a group receiving TNP-470 and a group receiving MMC. TNP-470 was given s.c. on alternate days for 5 weeks from day 10 after cecal transplantation and MMC was administered intraperitoneally (i.p.) once a week from day 10 after cecal transplantation. MMC significantly inhibited cecal tumor growth. In the control group, liver metastases developed in 9 out of 10 mice, including 3 with more than 20 metastatic foci. Liver metastasis also developed in 8 out of 10 mice receiving MMC, 2 of which had many metastases. In contrast, liver metastasis developed in only 2 out of 8 mice in the TNP-470 group and neither of these animals had numerous metastases.

Animals↗
PubMed1995

Detection of K-ras mutations in DNAs isolated from feces of patients with colorectal tumors by mutant-allele-specific amplification (MASA).

K-ras mutations are found in approximately half of all colorectal tumors examined. To explore the possibility of detecting mutated K-ras rapidly and efficiently in DNAs isolated from fecal material, we applied the mutant allele specific amplification (MASA)-PCR method to DNA from feces of patients with colorectal tumors. Among 55 colorectal adenocarcinomas or adenomas examined, 19 were found to carry K-ras mutations in codons 12 or 13. We were able to PCR-amplify DNAs isolated from feces of 15 of these 19 patients, but in only three of the fecal samples, we were able to detect the K-ras mutations corresponding to tumor DNA by MASA and ethidiumbromide staining of the gel. The carcinomas in these three cases were more than 40 mm x 40 mm in size and located in the sigmoid colon or rectum. However, we identified the K-ras mutations in fecal DNAs of additional seven patients by MASA when the gels were blotted and probed with a radio-labeled oligonucleotide; the tumors in those patients had arisen in the distal half of the colon and the smallest of these tumors was only 7 mm x 5 mm. No K-ras mutations were detectable in feces of the remaining five cases, whose tumors were relatively small and/or located in the proximal region. The results suggested that the MASA-PCR system has potential for development as a simple, rapid and noninvasive method for diagnosing the presence of colorectal tumors that carry mutant K-ras alleles, particularly tumors located in the distal colon.

Adenocarcinoma↗
PubMed1995

Expression and secretion of the beta subunit of human chorionic gonadotropin by bladder carcinoma in vivo and in vitro.

Expression and secretion of the beta subunit of human chorionic gonadotropin (hCG) by bladder carcinoma cell lines were investigated in vitro and in vivo. As an in vitro study, immunoreactive hCG beta (IR-hCG beta) secreted into the culture media of two bladder transitional cell lines (KoTCC-1 and HT-1197) was analyzed using three kinds of enzyme immunoassays which were specific for intact hCG, free hCG beta, and beta core fragment (beta-CF). Both of the cell lines were determined to secrete IR-hCG beta into the media, which consisted principally of free hCG beta, but detectable levels of intact hCG and beta-CF were not present in the media. Northern blot analysis revealed that the hCG beta gene was expressed in both KoTCC-1 and HT-1197 cells where the sizes of mRNA from these cells were smaller than those from placental and NJG choriocarcinoma cells. As an in vivo study, distribution of IR-hCG beta was analyzed in the tumor tissues, sera, and urine of the mice and the rats transplanted with KoTCC-1 cells. By the immunohistochemical study, the IR-hCG beta was clearly observed in transitional cell carcinoma cells of the transplanted tumor. High levels of IR-hCG beta were detected in both the serum and urine from the animals, but there were quantitative and qualitative differences between serum and urinary IR-hCG beta. Quantitatively, the concentrations of IR-hCG beta in the urine were consistently much higher than those in the serum. Qualitatively, free hCG beta was exclusively detected in the serum whereas high levels of beta-CF in addition to free hCG beta were found in the urine. Intact hCG could not be detected in the serum and urine. These distributions of IR-hCG beta in the animals transplanted with KoTCC-1 cells were completely analogous to those in a patient with hCG beta-producing bladder carcinoma. The present study shows that the same metabolic pathway of IR-hCG beta is operating in mice and rats as in humans, indicating that IR-hCG beta found in patients with bladder carcinoma originates from the tumor and it may be recognized as a tumor marker when beta-CF is measured in the patient's urine.

Animals↗
PubMed1995

Hepatic release of endothelin-1 after warm ischemia. Reperfusion injury and its hemodynamic effect.

This study investigated the release of endothelin (ET)-1 from the liver after warm ischemia/reperfusion (I/R) injury. Wistar rats were subjected to 120 min of warm hepatic ischemia by clamping the hepatic hilum under porto-jugular shunting. Reperfusion was performed by unclamping. The rats were divided into 2 groups receiving intravenous treatment with an anti-ET-1 mAb before ischemia (AET group) and with mouse immunoglobulin G (sham group). Hepatic blood flow was assessed by laser-Doppler flowmetry and reflectance spectrophotometry and was compared between the 2 groups along with the bile flow rate. The ET-1 concentrations of hepatic venous and portal blood were determined in the sham group, and the portal blood endotoxin levels were assayed in both groups. Both groups developed transient hypotension after reperfusion, but hepatic blood flow subsequently showed a significant improvement in the AET group. Hepatic congestion was detected in the sham group by both reflectance spectrophotometry and histological examination. After reperfusion, bile flow was significantly greater in the AET group. The portal endotoxin concentration showed no increase in both groups, and the hepatic venous blood ET-1 level in the sham group was significantly higher until 3 hr after reperfusion compared to the portal blood level. The 30-day survival rate was 50% in the AET group, whereas all the sham rats died within 12 hr. ET-1 was released from the liver after I/R injury and apparently participated in systemic and local hemodynamic changes that affected survival.

Animals↗
PubMed1995

Prevention of hepatic metastasis of human colon cancer by angiogenesis inhibitor TNP-470.

The antimetastatic effect of a potent angiogenesis inhibitor, O-(chloroacetyl-carbamoyl)fumagillol (TNP-470), was investigated in nude mice implanted with human colon cancer. Small pieces of tumors from three established human colon cancer cell lines (TK-3, TK-4, and TK-9), which were maintained in nude mice, were implanted into the cecal wall of nude mice via a small incision in the serosa. TNP-470 (20 or 30 mg/kg) was given s.c. every other day from day 10 after implantation, and the mice were sacrificed after 6 weeks. There was no difference in the weight of the implanted tumors (control group: 0.45 +/- 0.29 g versus treated group: 0.49 +/- 0.27 g). An antimetastatic effect of TNP-470 was clearly demonstrated in a dose-dependent manner. In the mice given 20 mg/kg TNP-470, liver metastasis developed in 3 of 10 cases. In the 30-mg/kg group, metastasis developed in only 1 of 17 mice, while it developed in 22 of 32 mice of the control group. The number of metastatic foci was significantly less in the treated groups. TNP-470 effectively prevented liver metastasis, however, but had no effect on the growth of the primary tumor. These results indicate that the angiogenesis inhibitor TNP-470 has a strong inhibitory activity against in vivo hepatic metastasis of human colon cancer.

Adenocarcinoma↗
PubMed1995

Purification and characterization of a non-hemorrhagic metalloprotease from Agkistrodon halys brevicaudus venom.

A non-hemorrhagic metalloprotease (protease L4) was purified from the venom of Chinese Mamushi (Agkistrodon halys brevicaudus) by gel filtration and anion-exchange chromatography. Protease L4 has the molecular weight of 22,000 and its optimum pH was 8.5. The protein was stable in the pH range of 5-9 and below 40 degrees C. The proteolytic activity was inhibited by metal-chelating agents and some metal ions. Calcium ion activated the activity dose-dependently, but had only a minor effect on the thermal and pH stability. L4 showed fibrinogenase activity, hydrolyzing only the A alpha chain of fibrinogen. The protease cleaved preferentially at the N-terminal of Leu and His residues of some peptides.

Agkistrodon↗
PubMed1995

Hepatocellular carcinoma associated with lupoid hepatitis: a review of Japanese reports.

A 66-year-old woman was diagnosed as having lupoid hepatitis due to the presence of hypergammaglobulinemia, lupus erythematosus cells, and positivity for antinuclear, anti-DNA, and anti-smooth muscle antibodies. None of the serum hepatitis B markers were positive. Symptomatic relief was obtained by prednisolone administration. Five years after the diagnosis of lupoid hepatitis, hepatocellular carcinoma (HCC) was detected by ultrasonography and computed tomography, after which hepatectomy was performed. Although transcatheter arterial embolization was done on two occasions and repeat hepatectomy was performed twice for recurrent HCC, her liver function remained good with the prednisolone treatment. Antibody for hepatitis C virus has been negative since our first check in 1992. As of this writing, the patient has been alive and well 6 years and 2 months after the first hepatectomy. There have been no previous reports of 6-year survival after hepatectomy for HCC associated with lupoid hepatitis.

Aged↗
PubMed1995

Prognostic significance of posterior subtalar joint arthrography following fractures of the calcaneus.

Nineteen patients with 22 intra-articular fractures of the calcaneus were investigated by posterior subtalar joint arthrography after 6 (2-15) months following injury, and their clinical symptoms were compared with the arthrographic findings. The arthrograms were classified into four types based on the findings of the joint space of the posterior subtalar joint in Anthonsen's view. The classification correlated significantly (P = 0.03) with the clinical results which were assessed after 23 (9-41) months following injury. We conclude that posterior subtalar joint arthrography has prognostic value in assessing patients with fractures of the calcaneus.

Adolescent↗
PubMed1995

Intrasellar neuronal choristoma associated with growth hormone-producing pituitary adenoma containing amyloid deposits.

The histological, immunocytochemical, and ultrastructural features of an intrasellar neuronal choristoma associated with pituitary growth hormone (GH)-producing adenoma are reported. Immunohistochemistry studies and electron microscopy examination showed the adenoma cells to be positive for GH but negative for prolactin, and the neurons of the choristoma to have GH-releasing factor (GRF) neurosecretory activity. The adenoma also had many amyloid deposits in its extracellular space immunoreactive to GRF. This is the first report of the tumor containing amyloid deposits.

Adenoma↗