Biomedical subjects

A Kanno

Publications and source records attributed to A Kanno.

At least 55 records · Page 3Linked to original sources

PubMed1996

Gustatory evoked magnetic fields in humans.

Magnetic fields evoked by taste stimuli of the human tongue were measured over the whole head using a helmet-shaped 64 channel magnetoencephalography system in five normal subjects. The stimuli were 10% glucose and 0.3 M NaCl solutions and distilled water. The most prominent peak (N175m) appearing over the bilateral hemispheres had a latency of 150-210 ms. The N175m sources were located using a two-dipole model in a spherical conducting medium based on the individual head dimensions and superimposed on magnetic resonance images. The N175m dipoles due to 10% glucose and 0.3 M NaCl stimuli were located at the operculum and circum-insular areas in both hemispheres, but those due to distilled water could not be located accurately.

Adult↗

PubMed1996

Neuromagnetic evidence of pre- and post-central cortical sources of somatosensory evoked responses.

Somatosensory evoked magnetic fields (SEFs), corresponding with electrical median nerve stimulation, were measured using an MRI-linked, whole-head MEG system. In total 184 hemispheres, SEFs were measured, involving 22 normal volunteers and 70 patients with intracranial lesions. The first SEF peak appeared 20.2 +/- 1.5 msec (mean +/- S.D.) after stimulation. The first peak was followed by a second and third peak, 7.7 +/- 3.2 msec and 14.6 +/- 5.4 msec respectively after the first. Corresponding isofield maps suggested a single current dipole oriented in the anterior direction for the first peak, posterior for the second and either anterior or posterior for the third. Using a spherical model and a single current dipole source, the localization of each peak was estimated and superimposed on individually determined MRI images. On a grand average basis, the first-peak dipole was localized on the posterior surface of the central sulcus, "area 3b." The second-peak dipole was localized 3.7 mm medial (P < 0.001) and 2.0 mm superior (P < 0.001) to the first-peak dipole, on the anterior wall of the central sulcus, "area 4." This study with a large number of subjects was able to statistically distinguish two adjacent cortical sources, located on opposite walls of the central sulcus, and within a few millimeters of each other.

Adult↗

PubMed1996

Cool-temperature-induced chlorosis in rice plants.

We have established an experimental system for mimicking the phenomenon of cool-temperature-induced chlorosis (CTIC) in rice plants (Oryza sativa L.). Rice seedlings were initially grown in darkness under cool-temperature conditions and then exposed to light and warm conditions to follow the expression of CTIC. Induction of CTIC in the sensitive cultivar (cv Surjamukhi) was bimodally dependent on the temperatures experienced during the initial growth in darkness. CTIC was maximally induced between 15 and 17 degrees C. A positive correlation was demonstrated between induction of CTIC and the growth activity of shoots during growth in darkness. Electrophoretic and immunoblot analysis revealed that accumulation of NADPH-protochlorophyllide oxidoreductase in plastids was also bimodally dependent on the temperatures during the growth in darkness with minimum accumulation between 15 and 17 degrees C, suggesting that the reduction of NADPH-protochlorophyllide oxidoreductase accumulation in plastids might be closely linked to a disturbance in transformations of plastids to etioplasts during the dark growth under the critical temperatures and thereby to the CTIC phenomenon. This was corroborated by electron microscopic observations. These results suggest that growth is one of the determining factors for the expression of CTIC phenotype in rice under cool temperature.

Amino Acid Sequence↗

PubMed1996

[Specific inhibitory effect of hybrid liposomes on the growth of hybridoma cells in vitro].

Remarkably high inhibitory effects of the hybrid liposomes composed of L-alpha-dimyristoyl-phosphatidylcholine (DMPC) and polyoxyethylenealkyl ether (C14(EO)n, n = 6-8 and C12(EO)n, n = 8-12)) on the growth of human lymphoma-human B-lymphocyte hybridoma (HF) cells in vitro were obtained. The hybrid liposomes composed of 90 mol% DMPC/10 mol% C14(EO)n (n = 6-8) or C12(EO)n (n = 8-12) were more fluid as compared with 90 mol% DMPC/10 mol% C14(EO)4 or C12(EO)n (n = 4, 23) hybrid liposomes on the basis of fluorescence polarization measurements. These results suggest that the inhibitory effects of the hybrid liposomes on the growth of HF cells should be related to the membrane fluidity. No toxicity to normal rats in vivo was observed in the experiment using 90 mol% DMPC/10 mol% C14(EO)7 or 90 mol% DMPC/10 mol% C12(EO)12 hybrid liposomes.

Animals↗

PubMed1996

Liver involvement in Tsutsugamushi disease.

Tsutsugamushi disease, one of the rickettsiosis, is known to be occasionally accompanied by elevation of hepatic enzyme levels. However, there are only a few reports on histopathological findings of the liver. We presented a case of Tsutsugamushi disease with liver involvement. A 51-year-old man suffered from eruptions and a high fever with a mild transaminasemia. He was diagnosed as Tsutsugamushi disease by detection of IgM class antibody against Rickettsia tsutsugamushi. Laparoscopic examination showed a dark-brown liver with diffuse whitish markings. Microscopic findings were consistent with the features of non-specific reactive hepatitis: sinusoidal small lymphocyte infiltrations, mild disarray of hepatocytes and aggregation of T lymphocytes and macrophages in the lobule.

Humans↗

PubMed1996

[Right hemispheric dominancy in the auditory evoked magnetic fields for pure-tone stimuli].

It is well known that the auditory evoked N100m response is dominant in the contralateral hemisphere to the stimulated ear: N100m latency is shorter and N100m amplitude is larger in the contralateral hemisphere than the ipsilateral hemisphere. Interhemispheric asymmetry of the N100m responses were reported in terms of the equivalent dipole localization: the right hemispheric N100m dipole is more anterior to the left hemispheric dipole. In the present study, we investigated interhemispheric asymmetry of the auditory evoked P50m and N100m response in terms of signal amplitude. A helmet-shaped whole head magnetoencephalography system was employed to see small but significant differences between two hemispheres. Thirty-seven right-handed healthy subjects, 31 males and 6 females, participated in the study. The helmet-shaped whole head MEG system (CTF Systems-Osaka Gas) consists of an array of 66 MEG sensor sites uniformly distributed over the entire head. The monaural auditory stimuli, 2000 Hz tone burst of 50 msec duration were delivered to the left and then the right ear sequentially, with an intensity of 80 dB SPL at the ear. White noise of 50 dB SPL was delivered to the opposite ear. The inter-stimulus intervals were randomized in the range from 2.5 to 4.7 sec. In a total of 37 subjects, N100m dipole pattern appeared on both hemispheres either left or right ear stimuli. When P50m peak amplitude was compared between contralateral responses, the right-hemispheric response (141.5 +/- 16.3 fT, mean +/- s.e.m.) was slightly larger than the left-hemispheric response (134.3 +/- 10.2 fT). Differences, however, were not significant. When P50m peak amplitude was compared between ipsilateral responses, the right-hemispheric response (135.1 +/- 11.0 fT) was slightly larger than the left-hemispheric response (115.3 +/- 10.9 fT). Differences were not significant, either. When N100m peak amplitude was compared between contralateral responses, the right-hemispheric response (484.4 +/- 28.4 fT) was statistically (p < 0.01) larger than the left-hemispheric response (375.6 +/- 28.0 fT). When N100m peak amplitude was compared between ipsilateral responses, the right-hemispheric response (405.8 +/- 27.9 fT) was statistically (p < 0.02) larger than the left-hemispheric response (315.1 +/- 24.8 fT). Previously, we reported that the right hemispheric latency is shorter than the left hemispheric latency in the auditory evoked field N100m responses. Present study indicated another evidence of the right hemispheric dominancy in the auditory evoked responses, namely the lager amplitude in the right hemispheric response at least for pure-tone stimuli. The whole-head MEG system is suitable to analyze differences of auditory function between two hemispheres.

Acoustic Stimulation↗

PubMed1996

Neuromagnetic evidence that the P100 component of the pattern reversal visual evoked response originates in the bottom of the calcarine fissure.

Visual evoked magnetic fields due to pattern reversal stimuli were measured in 5 normal subjects using a helmet-shaped 66 channel magnetoencephalography system linked to MRI. The magnetic topography of the prominent 100 ms response (P100m) evoked by fullfield visual showed a double-dipole pattern in the occipital areas of all subjects. Right or left half-field stimuli and upper or lower quadrant-field stimuli evoked a single-dipole pattern in the contralateral occipital area. The P100m sources were then localized using a current dipole model and superimposed on MRI images of each subject. The visual cortex was morphologically variable among the subjects, but the P100m dipoles were all localized at the lateral bottom of the calcarine fissure. Moreover, these P100m dipoles had similar orientations for both half-or quadrant-field stimuli. These results suggest that the P100m is located in a smaller part of the striate cortex than previously reported.

Adult↗

PubMed1996

[Auditory evoked magnetic fields in cases with temporal lobe glioma].

Auditory evoked magnetic field (AEF) is known to be suitable to separate left and right hemispheric activities while auditory evoked potential is not. To evaluate cortical auditory function in ten patients with temporal lobe gliomas, we measured AEF for monaural tone stimuli using a helmet-shaped 66-channel MEG system. Latency of the N 100 m, the most prominent peak with a latency around 90 ms, was measured in the hemisphere contralateral to the stimulus onset. In five patients, the N 100 m latency was within our normal range (mean +/- 2 s.d.). In these five cases, tumor was located in the anterior or the inferior part of the temporal lobe. We observed significant delay of the N 100 m latency in four patients and disappearance of the N 100 m in another patient. In the later five patients, tumor extended to the superior and posterior part of the temporal lobe. AEF can be used to evaluate cortical auditory function noninvasively in cases with temporal lobe gliomas.

Adult↗

PubMed1996

Clinical application of visual evoked fields using an MRI-linked whole head MEG system.

We have demonstrated anatomo-functional correlation of the brain visual function using an MRI-linked whole-head magnetoencephalography system. Visual evoked magnetic fields (VEFs) due to pattern reversal stimuli were measured in seven healthy subjects and 13 patients with intracranial structural lesions. Full-field stimuli evoked the most prominent peak around 100 ms latency (P100m) as a two-dipole pattern over the occipital area in all of the normal subjects and four patients with mild and partial hemianopsia. In five patients with homonymous hemianopsia due to unilateral occipital lesion, a single-dipole pattern of the P100m appeared over the normal occipital area only. In four patients with bitemporal hemianopsia due to pituitary tumors, a single-dipole pattern of the P100m appeared only over the ipsilateral occipital area to the stimulated eye. Using current dipole models, P100m sources were localized at the lateral bottom of the calcarine fissures. Although human occipital lobes are known to be morphologically variable, our results indicate excellent correlation of the cortical anatomy and human visual function. Full-field stimuli, requiring no strict visual fixation, are especially useful for clinical application. A clear two-dipole pattern in the normal VEFs enables us to compare two hemispheric activities.

Adult↗

PubMed1996

[Trial of home anti-cancer chemotherapy with infusion of 5-FU and low-dose cisplatin].

We tried home anti-cancer chemotherapy for patients with advanced or recurrent cancer of the digestive system, using two disposable balloon pumps connected to an implantable drug delivery system via central venous line. There were 33 patients under 75 years old, including 20 cases of gastric cancer, 9 cases of colorectal cancer, 2 cases of cholangiocarcinoma and 2 cases of esophageal cancer enrolled in this study. The protocol was combined chemotherapy with continuous intravenous infusion of 5-FU (300 mg/body/day) and low-dose intravenous injection of cisplatin (5 mg/body/day) in 10-day courses for two weeks, and it was repeated 3 times for 6 weeks. Because of side effects such as nausea, vomiting and bone marrow suppression, treatment was discontinued in 12 cases with peritoneal cancer infiltration. In two of 10 with estimable disease, the reduction of the metastatic lymph node was observed, but no effect was shown in the colorectal metastatic liver tumor. Thanks to the portability of the pump with this method, the patient need not undergo hospitalization. Moreover, there is no renal dysfunction or other major side effects, quality of life is not compromised and a return to family and social life is possible. Thus, if the patient cannot take the oral nutrition, it is easy to start home hyper-alimentation.

Aged↗

PubMed1996

[How to palliate the symptoms of terminally ill patients at home].

We reported the kind of symptoms and how they could be palliated in terminally ill patients at home based on our experience of about 9 years. Cancer pain, which was the most frequent symptom, appeared in 67 among 126 patients receiving home care, and it could be effectively controlled with morphine; no patient returned to the hospital because of aggravation of pain. Very few patients stayed in the hospital and never returned home due to uncontrollable pain. Home parenteral infusion was done for 63 patients who were unable to eat or drink because of peritonitis carcinomatosa or cancer cachexia. High fever in the tumor mass was controlled by glucocorticoid hormone, and ascites was drained continuously when the patients suffered from abdominal distension. From analysis of the cases in which home care was interrupted or those in which patients were unable to transfer to home care, symptoms that were difficult to palliate at home were nausea caused by bowel obstruction, acute symptoms (bleeding, disturbance of consciousness, and so on), and dyspnea. But if the patients and family are eager for home care and an adequate medical support system is in place, home care may be possible despite these symptoms.

Hospice Care↗

PubMed1996