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Biomedical subjects

I Suzuki

Publications and source records attributed to I Suzuki.

At least 253 records · Page 14Linked to original sources
PubMed1988

Distribution of grifolan NMF-5N (I/B), a chemically modified antitumor beta-glucan in mice.

The distribution of a 3H-labeled chemically modified antitumor beta-glucan, grifolan NMF-5N (I/B), in various tissues after an injection into mice was examined in order to obtain information on distribution of the parent antitumor beta-glucan, grifolan NMF-5N. Grifolan NMF-5N was treated with sodium metaperiodate and sodium borotritide to obtain tritium-labeled grifolan NMF-5N [3H-grifolan (I/B)]. When 3H-grifolan (I/B) was administered into normal mice by intraperitoneal (i.p.) or intravenous (i.v.) injection, radioactivity was detected in various mouse tissues. Next, 3H-grifolan (I/B) was injected into tumor-bearing mice 7 d after the tumor inoculation, which is the most effective administration timing for the antitumor effect of grifolan NMF-5N. The results indicated a strong radioactivity in spleens and tumor masses. These results suggested a close relationship between the antitumor activity and the distribution of grifolan NMF-5N in mice.

Animals↗
PubMed1988

The effects of a highly branched beta-1,3-glucan, SSG, obtained from Sclerotinia sclerotiorum IFO 9395 on the growth of syngeneic tumors in mice.

The effects of a highly branched beta-1,3-glucan, SSG, obtained from a culture filtrate of a fungus, Sclerotinia sclerotiorum IFO 9395, on the growth of syngeneic tumors and antitumor effector cells were examined. In the Meth A solid tumor systems, SSG administered intraperitoneally (i.p.), intralesionally (i.l.), or intravenously (i.v.) showed significant antitumor activities. Furthermore, SSG administered i.p. also showed effective activities against IMC carcinoma. SSG enhanced nonspecific antitumor effector functions, such as natural killer activity of spleen cells and the cytolytic activity of peritoneal macrophages. Additionally, SSG increased the specific immune response (cytotoxic T lymphocyte activity) against allogeneic tumor cells.

Animals↗
PubMed1988

Alpha 1-acid glycoprotein and hepatic fibrosis.

The relationship between alpha 1-acid glycoprotein (alpha 1-AG) and liver fibrosis was studied. Immunoperoxidase staining of liver specimens from patients with chronic hepatitis showed large amounts of alpha 1-AG to be located primarily in hepatocytes adjacent to areas of piecemeal necrosis, bridging fibrosis and fibrous septa. In patients with severe chronic active hepatitis, hepatocytes throughout the liver stained similarly to those adjacent to areas of piecemeal necrosis. In cell cultures of human embryonal lung (HEL) fibroblasts, addition to the culture medium of alpha 1-AG promoted cell growth. It is known that alpha 1-AG is also produced in the liver. It thus appears likely that alpha 1-AG is a promoter of hepatic fibrosis in chronic hepatitis.

Adolescent↗
PubMed1988

[Microorganisms isolated from urinary tract infection and their beta-lactamase production and evaluation of clinical efficacy of sulperazone].

Clinical survey of microorganisms isolated from urinary tract infection (UTI) was carried out at the four major hospitals in Mie Prefecture from May to July, 1987, and production of beta-lactamase of the microorganisms was determined by the acidimetric method, "beta-checker". Among the total of 460 strains isolated from urine samples, 135 of gram positive cocci and 325 of gram negative rods were contained. Sixty percent of the gram negative rods and 14% of gram positive cocci produced beta-lactamase. Pseudomonas aeruginosa, E. coli and Serratia marcescens were representative organisms which produced beta-lactamase. Acinetobacter, Klebsiella, Enterobacter and Citrobacter species produced beta-lactamase at a higher rate but those were not so frequently isolated. In the sensitivity test to Sulperazone, the representative organisms isolated from urine, as a whole, had a sensitivity of 74% and E. coli, Klebsiella, S. epidermidis and Pseudomonas aeruginosa were highly sensitive, while Enterobacter cloacae and Serratia marcescens showed low sensitivity. The clinical efficacy of Sulperazone was evaluated in 26 patients with complicated UTI. Overall effectiveness rate and eradication rate of beta-lactamase production organisms were 73.1 and 63%, respectively. Sulperazone is concluded to be a useful antibiotic for treating complicated UTI induced by beta-lactamase production organisms from the point of microbiology and safety.

Adult↗
PubMed1988

[Early detection of central nervous system dysfunction during cardiopulmonary bypass using EEG monitoring].

The EEG was monitored in fifty-four patients during and after various surgeries requiring cardiopulmonary bypass (CPB) to assist in the early detection of central nervous system dysfunction (CNSD). Bilateral frontopolar EEG signals were processed with a 2-channel, real-time Fast-Fourier-Transformer (FFT) analyser and Compressed Spectral Arrays (CSA) were obtained. The fifty-four patients were divided into 3 groups based upon clinical outcome; Group 1: patients without CNSD (83%); Group 2: patients with delayed recovery from anesthesia but without CNSD (4%); and Group 3: patients with apparent postoperative CNSD (13%). There was no difference in the CSA among these groups prior to rewarming, but after the rewarming phase, two distinct sets emerged. Groups 1 and 2 showed a shift of the CSA predominant peak from a low frequency to a higher frequency. On the other hand, Group 3 patients demonstrated either stable predominant peaks in the lower frequencies or gradual flattening of the CSA. We conclude that the intra-operative EEG monitoring is a useful tool for the early detection of CNSD during and after CPB.

Adult↗
PubMed1988

[Cortical and subcortical somatosensory evoked potentials to median nerve stimulation in man].

In order to define the precise locations of precentral and postcentral gyri during neurosurgical operations, somatosensory evoked potentials to contralateral median nerve stimulation were recorded from the cerebral cortex in 19 cases with organic cerebral lesions which located near the central sulcus. In addition to that, distribution patterns of early components of SEPs were displayed by Nihonkoden Atac 450 in 3 cases who had bone defects after wide decompressive craniectomy but were without any sensory disturbances In 4 cases, in whom deep electrodes were inserted for the stereotaxic operations or other reasons, frontal subcortical SEPs were recorded in order to know the origins of frontal components of SEPs. From the parietal cortex, N19, P22 and P23 were observed. And from the frontal cortex, P20 and N25 were obtained. Their average peak latencies were as follows; (table; see text) Because all subjects had organic lesion in the brain, the peak latencies were a little bit longer, and their standard deviations were larger than those in normal cases. Usually, clear-cut phase reversal could be observed between N19 and P20 across the central sulcus. So, the precentral and postcentral gyri were easily identified during the operations. N19 and P23 appeared over the wide areas of the parietal cortex. Also, P20 and N25 were recorded almost whole areas of the frontal cortex. On the other hand, P22 appeared from relatively restricted part of the postcentral gyrus where sensory hand area might have been located. Depth recording from the frontal subcortical area revealed that P20 could be recorded from the bilateral frontal subcortical areas and there observed no phase reversal between the cortical and subcortical SEPs.(ABSTRACT TRUNCATED AT 250 WORDS)

Brain Diseases↗
PubMed1987

A quantitative study of physiological cerebral atrophy with aging. A statistical analysis of the normal range.

A new method of discriminating pathological cerebral atrophy from physiological atrophy during aging is reported. The authors advocate a pixel counting method using a minicomputer for the quantitative measurement of cerebral atrophy. Five hundred cases were studied with this quantitative method and the normal range of the physiological atrophy was determined statistically. In order to estimate the degree of cerebral atrophy easily, the conventional linear measurement methods were compared with the pixel counting method using multivariant analysis, and a simple formula for the calculation of the degree of cerebral atrophy is proposed. Using this formula and the normal range, pathological cerebral atrophy is easily detectable.

Adolescent↗
PubMed1987

Recurrent inhibitory connexions among neck motoneurones in the cat.

1. Intracellular recordings were made from motoneurones innervating neck muscles in the cat. Dorsal roots were cut and muscle nerves electrically stimulated to activate alpha motor axons. 2. Recurrent inhibitory post-synaptic potentials (i.p.s.p.s) evoked by antidromic volleys in homonymous or heteronymous nerves were found in the majority of motoneurones studied, including those to dorsal neck muscles (biventer cervicis, splenius and complexus) as well as to occipitoscapularis and levator scapulae ventralis. 3. Central latencies of the recurrent i.p.s.p.s indicate disynaptic transmission. Amplitudes ranged from 100 microV (criterion level) to 2.2 mV. Average amplitudes were less than 0.6 mV. 4. The recurrent i.p.s.p.s were distributed to non-synergistic as well as to synergistic motoneurones. Analysis of relative strength of recurrent inhibition indicates influence of proximity of motoneurone pools, functional relatedness of muscles, as well as other factors. Variation in intrinsic motoneuronal properties probably underlies positive correlations (independent of variation in resting potential) between recurrent i.p.s.p.s evoked from different sources in motoneurones of a single pool. 5. Recordings (mainly extracellular) were also made from interneurones (Renshaw cells), located in the C3 and C4 segments of the spinal cord, that were excited by antidromic volleys in muscle nerves. The response varied from a single action potential to a burst of up to nineteen action potentials. Central latencies to the first response indicate monosynaptic transmission. Many Renshaw cells were excited by antidromic volleys in several muscle nerves, though this was restricted to nerves of the same segmental level as the Renshaw cell. All the muscle nerves studied were effective in activating Renshaw cells. 6. The results indicate that in many ways the recurrent i.p.s.p.s and the responses of Renshaw cells recorded in the neck segments resemble those in the hind-limb segments. Thus, the basic organization of recurrent inhibition in the neck segments resembles that occurring elsewhere in the spinal cord. A difference is the tendency for recurrent i.p.s.p.s in neck motoneurones to be relatively small in amplitude and Renshaw cell responses to be less strong than those recorded in the hind-limb segments. It is suggested that this is related to the segmentation of neck muscles and their motoneurone pools. 7. It is concluded that recurrent inhibition is a prominent feature of spinal organization governing neck muscles. It can therefore be expected to participate in control of head movements.

Action Potentials↗
PubMed1987

Control of abdominal and expiratory intercostal muscle activity during vomiting: role of ventral respiratory group expiratory neurons.

The role of ventral respiratory group (VRG) expiratory (E) neurons in the control of abdominal and internal intercostal (expiratory) muscle activity during vomiting was examined in decerebrate cats by recording from these neurons during fictive vomiting in paralyzed animals and comparing abdominal muscle activity during vomiting before and after sectioning the axons of these descending neurons. Fictive vomiting was defined by a series of bursts of coactivation of abdominal and phrenic nerves elicited by either subdiaphragmatic vagus nerve stimulation or emetic drugs. Such coordinated activity would be expected to produce vomiting if the animals were not paralyzed. Data were recorded from 27 VRG E neurons that were antidromically activated from the lower thoracic (T13) or lumbar spinal cord. During fictive vomiting, almost two-thirds of these neurons (17/27) were mainly active in between periods of abdominal and phrenic nerve coactivation, when the internal intercostal motoneurons are known to be active. This group of neurons was termed INT neurons. INT neurons were subdivided according to whether they were active between every burst of phrenic and abdominal nerve coactivation (INTa neurons, n = 10) or only between some bursts (INTb neurons, n = 7). Another one-third of the VRG E neurons had normal or increased levels of activity when the abdominal nerves were active during fictive vomiting (ABD neurons). The one remaining neuron was mainly silent throughout fictive vomiting. ABD neurons were indistinguishable from INT neurons on the basis of their location in the VRG, type of firing pattern (ramp versus step ramp), conduction velocity, or extent of projection in the lumbar cord. However, INTa neurons had a significantly higher discharge rate during respiration than either ABD or INTb neurons. Abdominal muscle EMG and nerve activity were recorded from six unparalyzed cats before and after cutting the axons of VRG E neurons as they cross the midline between C1 and the obex. The lesions abolished or almost eliminated expiratory modulation of abdominal muscle activity. In contrast, the abdominal muscles were always active during vomiting; however, the amplitude of postlesion abdominal activity varied from approximately 70-100% of prelesion values in three cats to 60-70% of normal in a fourth animal to only approximately 20% of prelesion values in two other cats.(ABSTRACT TRUNCATED AT 400 WORDS)

Abdominal Muscles↗
PubMed1987

Host-mediated antitumor effect of grifolan NMF-5N, a polysaccharide obtained from Grifola frondosa.

The antitumor mechanism of grifolan NMF-5N, a beta-1,3-glucan obtained from mycelia of Grifola frondosa, was examined. Grifolan NMF-5N did not show direct cytocidal effect on cultured tumor cells. However, intraperitoneal injection of grifolan NMF-5N increased the number of peritoneal exudate cells and peritoneal adherent cells which showed cytostatic activity towards syngeneic tumor cells. In an in vivo assay, the administration of carrageenan, an inhibitor of macrophage function, reduced the antitumor activity of grifolan NMF-5N. The delayed-type hypersensitivity reaction was augmented in the grifolan NMF-5N-administered mice. The administration of NMF-5N augmented the induction of cytotoxic T cells but the antitumor activity of grifolan NMF-5N was reduced in athymic nu/nu mice. In addition, the treatment with anti-Thy 1,2 antibody and complement C' of spleen cells taken from mice which showed regression of tumor due to grifolan NMF-5N, reduced the neutralizing effect in Winn assay. These results suggested that grifolan NMF-5N shows antitumor activity via host-mediated mechanisms and both macrophages and T cells play important roles in the mechanisms.

Animals↗
PubMed1987

Antitumor effect of polysaccharide grifolan NMF-5N on syngeneic tumor in mice.

Antitumor activity of grifolan NMF-5N, a beta-1,3-glucan obtained from mycelia of Grifola frondosa, was examined. Grifolan NMF-5N showed antitumor activities in allogeneic and syngeneic murine tumor systems. In the allogeneic tumor system, a potent antitumor activity over 95% was observed against the solid form of sarcoma 180 when grifolan NMF-5N was injected intraperitoneally (i.p.) at 25-200 micrograms/mouse daily for 10 successive days. In the syngeneic tumor systems, significant antitumor activities were observed against Meth A fibrosarcoma and MM 46 carcinoma by injection at 100 micrograms/mouse daily for 5 successive days, especially i.p. injection at day 7-11, when the tumor cells were inoculated subcutaneously (s.c.) on day 0. Moreover, when grifolan NMF-5N was injected i.p. every other week, significant antitumor activity was also observed. In addition, a single treatment with grifolan NMF-5N at 500 micrograms/mouse showed antitumor activities. Grifolan NMF-5N exhibited antitumor activities against these two syngeneic tumors by intraveneous (i.v.) injection. However, a marked inhibitory activity was observed by intratumorous (i.t.) injection against Meth A fibrosarcoma but not against MM46 carcinoma. These results suggest that antitumor activities of grifolan NMF-5N in murine syngeneic tumor systems depend on not only dosage but also injection routes and timing.

Animals↗
PubMed1987

Selective inhibition of erythropoiesis by sera from patients with chronic renal failure.

The pathogenesis of anemia in patients with chronic renal failure was studied by analyzing the effect of uremic sera on the in vitro colony growth of erythroid (CFU-E) and granulocyte-macrophage (CFU-GM) progenitor cells. Uremic sera from 20 of 30 patients inhibited erythroid colony growth below 70% of control even when cultured with normal human bone marrow of the same blood type. On the other hand, only one of the sera inhibited colony growth of CFU-GM as compared with normal sera. On Sephadex G-15 gel filtration, the CFU-E-inhibiting activity appeared in two different fractions: the void volume peak and the delayed eluant before the second peak. The inhibiting activity in the former fraction was noted only in uremic sera. The results of this study suggest the existence of a serum inhibitor(s) of erythropoiesis with a relative molecular mass of more than 1500 Da which are virtually impossible to dialyze by conventional membranes.

Anemia↗