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Biomedical subjects

Y Sano

Publications and source records attributed to Y Sano.

At least 361 records · Page 20Linked to original sources
PubMed1984

Effects of alpha-difluoromethylornithine on the growth of 9L rat brain tumor multicellular spheroids and their response to 1,3-bis(2-chloroethyl)-1-nitrosourea.

9L rat brain tumor cell spheroids were treated with alpha-difluoromethylornithine (DFMO) and 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) alone and in combination. In contrast to results obtained with 9L monolayer culture cells, very low concentrations of DFMO killed spheroid cell within 0.5 day after the start of treatment; cell kill was maximum within 2 to 3 days. DFMO cytotoxicity could be prevented by adding putrescine (to a final concentration of 1 mM) to the culture medium. DFMO also significantly slowed and eventually stopped the growth of spheroids in a dose-dependent manner. Cells in all regions of DFMO-pretreated spheroids were sensitized to BCNU as measured by colony-forming efficiency; this sensitization was prevented when putrescine was added to culture medium before BCNU treatment. When used as single agents, either a 3-day treatment with 10 mM DFMO or a 1-hr treatment with BCNU (1.5 micrograms/ml) produced similar growth delay, but used in combination, the two agents produced a much longer growth delay than produced by either agent alone. Growth of spheroids treated continuously for up to 28 days with 10 mM DFMO ceased at approximately 7 times the volume at the time of treatment. When spheroid cells were treated for 1 hr with BCNU (1.5 micrograms/ml) and then were treated continuously with DFMO, growth plateaued at approximately 3.5 times the volume at the time of treatment; when spheroids were treated first with DFMO for 3 days, then with BCNU (1.5 micrograms/ml) for 1 hr, and then treated continuously with DFMO, growth plateaued at approximately 1.5 times the volume at the time of treatment. The number of clonogenic cells per spheroid that survived combination treatment also reflected the cytotoxic effects of the two drugs. Thus, the combined drug treatment was very effective in inhibiting the growth of spheroids and in preventing an increase in the number of clonogenic cells per spheroid.

Animals↗
PubMed1984

Combination therapy with 1,3-bis(2-chloroethyl)-1-nitrosourea and low dose rate radiation in the 9L rat brain tumor and spheroid models: implications for brain tumor brachytherapy.

We studied the effects of combination treatment with 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) and low dose rate radiation in the 9L rat brain tumor in vivo model and the 9L multicellular tumor spheroid model. F-344 rats bearing intracerebral 9L gliosarcomas were implanted with removable 125I sources. Minimal (peripheral) tumor doses of 6387 rad produced an increased life-span (ILS) of 28% over that of control rats implanted with dummy sources, BCNU alone (13.3 mg/kg) produced in an ILS of 67%, and combination treatment with BCNU and implanted 125I sources produced an ILS of 167%. As measured by a colony-forming efficiency assay, the greatest cell kill in 9L spheroids occurred when BCNU was administered 24 hours before irradiation from a 137Cs source at a low dose rate of 5 rad/minute. At a higher dose rate of 210 rad/minute, the time dependence of the effects of combination treatment was identical and therefore independent of dose rate.

Animals↗
PubMed1984

Response of 9L rat brain tumor multicellular spheroids to single and fractionated doses of 1,3-bis(2-chloroethyl)-1-nitrosourea.

This study was designed to examine the relative effect of each of four fractions of 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) against 9L rat brain tumor multicellular spheroids and to compare the results of the cell survival and growth delay assays. Similar levels of cell kill resulted when BCNU was administered either as single fractions of 1.5, 3.0, 4.5, or 6.0 micrograms/ml for 1 hr or as one to four fractions of 1.5 micrograms/ml that were administered sequentially for 1 hr each. Survival was increased if the assay was delayed until 24 hr after drug treatment, which indicates that 9L cells in spheroids recover from BCNU-induced potentially lethal damage. When BCNU was administered in 1.5-micrograms/ml fractions, plating efficiencies depended markedly on the interval between the fractions. The 12-hr protocol produced an overall higher cell kill. Fractionation schedules of 24 and 36 hr produced less cell kill than did the other schedules. Survival plateaued for the last three treatments with BCNU in the 36-hr schedule. Cells in S phase at the time of administration of the initial 1.5-micrograms/ml fraction of BCNU moved into G1- and G2-M phases by 12 hr after treatment. For time periods longer than 12 hr, cells began to appear in the BCNU-resistant S phase. Thus, the movement of cells into the drug-sensitive and -resistant phases after the first fraction correlates well with the corresponding overall cytotoxic effect produced by treatment with the combined BCNU (1.5 micrograms/ml) fractions. For a higher concentration (3.0 micrograms/ml for 1 hr), maximum cell kill was reached within the 12- to 18-hr interval, after which cell kill plateaued. Cells were not found in the S-phase fraction 12 to 36 hr after the first treatment with 3.0 micrograms/ml; maximum cell kill for the fractionated protocols resulted at these times. Therefore, BCNU, which is classified as a cell cycle-nonspecific drug, can induce a partial synchrony in 9L spheroid cells, which determines the overall cytotoxicity produced by fractionated BCNU protocols. Although spheroids did not shrink during or after exposure to BCNU, growth was retarded by treatment with all doses and schedules. An optimum time point for growth delay measurement could not be determined from the data. However, correlations between cell survival and growth delay were obtained with arbitrarily chosen end point volumes of four and ten times the volume at the time of treatment.

Animals↗
PubMed1984

Study on C3-like factor in the serum of a C3-deficient subject.

Analysis of the serum of an individual having a deficiency of C3 (C3D) revealed that despite the fact that the C3 could not be detected immunochemically, a small amount of C3 haemolytic activity and total complement activity was indeed found to be present. The present study was performed to analyse the C3-like factor, responsible for this C3 activity in C3D serum. It was found that the C3-like factor was not neutralized by anti-C3 but was neutralized by anti-C5. The electrophoretic mobility of the C3-like factor corresponded to that of purified C5. Thus, C3-like factor was shown to have the antigenicity and electrophoretic mobility of C5. This factor was found in the sera of three other C3D subjects and even in pooled normal human serum (NHS). These findings suggest that, in cases of C3D, C5 compensates for the genetic lack of C3 and serves a protective function and that sensitized erythrocytes (EA) may be lysed by complement components without participation of C3.

Complement C3↗
PubMed1984

[Lipids metabolism of the patients with subarachnoid hemorrhage due to ruptured intracranial aneurysm, in comparison with other cerebrovascular diseases].

Lipids metabolism has been extensively studied in the large number of patients with hypertensive cerebral hemorrhage or cerebral infarction, however, the patients with subarachnoid hemorrhage due to ruptured intracranial aneurysm were customarily excluded from the study. Total cholesterol, LDL-cholesterol, HDL-cholesterol, triglyceride and atherogenic index were determined in 40 cases, who had undergone surgical treatment for ruptured intracranial aneurysm in various locations, and the results were compared with the data obtained from 20 operative cases with hypertensive cerebral hemorrhage, 40 cases with non-operative cases with hypertensive cerebral hemorrhage, 60 cases with cerebral infarction and 20 cases of cerebral lesions other than cerebrovascular disease (non-CVA). Serum levels of LDL-cholesterol and atherogenic index were significantly correlated with the preoperative grading of subarachnoid hemorrhage when compared with non-CVA (p less than 0.05). Total cholesterol, LDL-cholesterol and atherogenic index were well correlated with operative morbidity and active daily life (ADL) in the follow-up study of the patients with intracranial aneurysm, where the higher value of cholesterol indicated the poorer risk of the patients. In our present study, none of the data was found significant, when compared with non-CVA, in the other groups of cerebrovascular diseases except for the HDL-cholesterol, which was found significantly in low level in the group of cerebral infarction (p less than 0.001). Triglyceride was found elevated in the group of hypertensive hemorrhage indicating negative correlation to the severity, and rather similar pattern was seen in the subarachnoid hemorrhage, however, the data were not conclusive.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral Hemorrhage↗
PubMed1983

Phasically firing neurons in the supraoptic nucleus of the rat hypothalamus: immunocytochemical and electrophysiological studies.

Relations between firing patterns and peptides in supraoptic neurons of rat hypothalamic slice preparations were studied by electrophysiology, intracellular fluorescent dye-marking and immunocytochemistry. Seven out of 10 magnocellular neurons which showed phasically firing patterns were identified by injections of Lucifer Yellow-CH (LY); these were also stained with an anti-vasopressin serum. This report presents direct evidence that most of the phasically firing neurosecretory neurons in the supraoptic nucleus contain vasopressin. This study demonstrates the feasibility of combining immunocytochemical and electrophysiological techniques to study the peptides contents of single mammalian neurons.

Animals↗
PubMed1983

Identification of serotonin- and vasopressin immunoreactivities in the suprachiasmatic nucleus of four mammalian species.

The distribution of serotonin- and vasopressin immunoreactivities in the suprachiasmatic nucleus (SCN) of four mammalian species was studied with the use of the modified peroxidase-antiperoxidase (PAP) method and antisera to serotonin and vasopressin. In the SCN of the rat, hamster and cat, we noted a large number of serotonin-immunoreactive nerve fibers particularly in the ventral area, where these fibers containing small varicosities (less than 1 micron in diameter) formed a dense plexus. In the monkey (Macaca fuscata), however, only few serotonin-containing fibers were evident throughout the SCN. Vasopressin-immunoreactive somata and fibers were distributed in large numbers in the SCN of the rat, hamster, cat and monkey, especially in the dorsal nuclear area. Regional and species-related differences of serotonin- and vasopressin distribution in the SCN were elucidated; possible functional differences between the ventral and dorsal areas of the SCN are discussed.

Animals↗
PubMed1983

Immunohistochemical identification of neurons containing corticotropin-releasing factor in the rat hypothalamus.

A specific rabbit anti-CRF serum and the immunoperoxidase technique were used to show that CRF-containing neurons are mainly distributed in the paraventricular and supraoptic nuclei of the rat hypothalamus. In addition, immunoreactive neurons are scattered in other hypothalamic regions. These neurons are 20--30 micrometers in diameter. From the present and previous investigations it may be concluded that the hypothalamic magnocellular nuclei, i.e., paraventricular and supraoptic, and other hypothalamic accessory nuclei, are the producing sites not only for vasopressin and oxytocin, but also for corticotropin-releasing factor.

Animals↗
PubMed1983

Differences in the distributional pattern of CRF-, oxytocin-, and vasopressin-immunoreactive nerve fibers in the median eminence of the rat.

Conspicuous differences in the distributional pattern of nerve fibers containing corticotropin-releasing factor (CRF) or posterior lobe hormones, respectively, were shown in the median eminence of the adult male rat by means of immunoperoxidase histochemistry, with the use of anti-CRF, anti-oxytocin, and anti-vasopressin sera. In the rostral and central divisions of the median eminence, a high concentration of CRF-immunoreactive nerve fibers was found in the median portion of the external layer; these fibers terminated on the capillary loops of the hypophysial portal system. In the caudal division of the median eminence, the CRF-immunoreactive nerve fibers were located in the median to paramedian portions of the external layer. Numerous oxytocin- and vasopressin-immunoreactive nerve fibers were observed evenly distributed throughout the internal layer of the median eminence. In the external layer, a small number of the oxytocin- and vasopressin-containing nerve fibers was found around the capillary loops, particularly in the median to paramedian portions. The distributional patterns of the CRF and the posterior lobe hormones in the hypothalamo-hypophysial system and their functional interrelationship are discussed.

Animals↗
PubMed1983

Immunohistochemical demonstration of serotonin-containing nerve fibers in the inferior olivary complex of the rat, cat and monkey.

By the use of a modified peroxidase-antiperoxidase immunohistochemical method, the distribution of serotonin-containing nerve fibers was studied in the inferior olivary complex of the rat, cat and monkey. The entire inferior olivary complex of all three species contained serotonin fibers, and species-related differences in the distribution of serotonin fibers were observed. In the rat, the overall density of serotonin fibers was sparser than that in the other two species; the highest concentration of varicose serotonergic fibers was noted in the lateral portion of the dorsal accessory olive. In the cat, the densest distribution of serotonin fibers occurred in the caudal portion of the medial accessory olive, the dorsomedial cell column and the lateral portion of the dorsal accessory olive, where intervaricose segments of serotonin-immunoreactive fibers were not so distinct. In the monkey, the caudal medial accessory olive, the lateral portion of the dorsal accessory olive and the dorsal as well as the lateral lamella of the principal olive showed a maximum density of serotonin fibers. Apart from the influence of afferent serotonergic projections to the cerebellum, serotonergic neurons of the brainstem are considered to affect Purkinje cells via neurons of the inferior olivary complex projecting to the cerebellum particularly in the cat and monkey.

Animals↗
PubMed1983

CRF-immunoreactive nerve fibers in the circumventricular organs of the monkey, Macaca fuscata.

The occurrence of CRF (corticotropin-releasing factor)-immunoreactive nerve fibers in the circumventricular organs of adult male monkeys, Macaca fuscata, was studied on serially sectioned brains, by means of the peroxidase-antiperoxidase technique in combination with a highly specific and sensitive CRF antiserum. CRF-containing nerve fibers were found in high concentrations in the infundibulum and, in addition, in small numbers in the posterior lobe, organum vasculosum laminae terminalis, subfornical organ, and area postrema; they were missing in the pineal body and the subcommissural organ. The CRF-immunoreactive nerve fibers distributed in these organs were located in the proximity of the blood vessels.

Animals↗
PubMed1983

Immunohistochemical study on the localization of serotonin fibers and terminals in the spinal cord of the monkey (Macaca fuscata).

A modified procedure of PAP-immunohistochemistry with the use of a rabbit antiserum against serotonin was applied to investigate the pattern of serotonin-containing nerve fibers in the spinal cord of the monkey, Macaca fuscata. The majority of descending serotonin fibers in the white matter is located immediately below the pia mater in the ventrolateral funiculi. Lamina I and the outer zone of lamina II are supplied with numerous serotonin fibers. In the intermediate gray, two prominent bundles composed of longitudinal fibers, i.e., lateral and medial longitudinal serotonin bundles, were recognized at the lateral column and in the vicinity of the central canal, respectively. The motoneurons of the anterior horn are encompassed by fine networks of serotonin fibers and terminals. The results obtained from studies with the monkey spinal cord closely resemble those characteristic of the dog spinal cord as presented in a previous paper, except for portions of the lumbar level. In segments L3-L4, intercalated cell groups between the medial and lateral motor nuclei receive particularly rich inputs of serotonin fibers in the same manner as the neurons of the nucleus intermediolateralis. This peculiar finding may suggest the presence of a specialized nucleus in the anterior column of the simian and also human spinal cord.

Animals↗
PubMed1983

Morphological studies on neuroglia. VII. Distribution of "brain macrophages" in brains of neonatal and adult rats, as determined by means of immunohistochemistry.

Immunohistochemical studies with the use of the peroxidase-antiperoxidase (PAP) method revealed that "amoeboid microglial cells", in the brains of neonatal rats and "brain macrophages" in lesioned brains of adult rats react positively to an antiserum raised against macrophages. In brains of neonatal rats, "amoeboid microglial cells" stained by means of the PAP-method were observed in the corpus callosum, internal capsule, dorso-lateral region of the thalamus, subventricular zone of the lateral ventricle, and the subependymal layer of the ventricular system. These cellular elements were not detected in brains of rats aged 21 days or older. Resting microglial cells displaying a typical ramified structure were not specifically stained. Cells reacting positively to the macrophage antiserum appeared (i) in the cerebral cortex of adult rats following placement of a stab wound, or (ii) in the hippocampal formation after kainic acid-induced lesions; in the damaged areas immunoreactive cells exhibited the typical features of "brain macrophages". "Brain macrophages" and "amoeboid microglial cells" are considered to belong to the class of exudate macrophages derived from blood monocytes. Thus, elements of hematogenous origin do exist in the intact brain parenchyma of neonatal rats and in lesioned brains of adult rats. The relationship between brain macrophages and resting microglial cells is discussed.

Animals↗
PubMed1983

distribution of monoamine-containing nerve fibers in the pineal organ of untreated and sympathectomized dogs. Fluorescence- and immunohistochemical studies.

Monoamine (noradrenaline and serotonin)-containing nerve fibers distributed in the pineal organ of the dog were studied by means of histochemistry (formaldehyde-induced fluorescence) and immunohistochemistry (peroxidase-antiperoxidase-PAP method) with the use of a serotonin antiserum. With the fluorescence-histochemical technique a dense network of blue-green fluorescent fibers was demonstrated in the pineal organ. Most of these fibers formed a perivascular plexus and their branches penetrated into the intercellular spaces of the parenchymal cells. Since these fibers completely disappeared ten days after bilateral removal of the superior cervical ganglia, it was confirmed that they are noradrenergic post-ganglionic sympathetic nerve fibers. A few yellow-fluorescent fibers were detected in the proximal part of the organ after ganglionectomy. By the use of the PAP method, intensively immunoreactive parenchymal cells and nerve fibers were demonstrated. The distribution pattern of these fibers was similar to that of the fluorescent sympathetic fibers. After almost all immunopositive fibers had been abolished by sympathectomy, some serotonin-containing fibers remained. The latter could be traced back to a system of serotonin fibers in the epithalamic region. These findings suggest that 1) the sympathetic noradrenergic fibers in the pineal organ of the dog take up serotonin which is released from the pinealocytes, and 2) this organ receives a dual monoamine innervation via peripheral noradrenergic and central serotonergic nerve fibers.

Aging↗
PubMed1983

Immunohistochemical demonstration of serotonin nerve fibers in the hypothalamus of the cat.

Distribution of serotonin nerve fibers in the hypothalamus of the cat was studied using the peroxidase antiperoxidase (PAP) immunohistochemical method. There was a heavy concentration of serotonin nerve fibers in the nucleus suprachiasmaticus, the nucleus ventromedialis and the nucleus dorsomedialis. The distribution pattern of the serotonergic fibers in the cat was principally similar to that of the rat and monkey. However, species differences were noted in the mamillary complex, the nucleus hypothalamicus anterior, the nucleus paraventricularis and the nucleus supraopticus.

Animals↗
PubMed1983

The organization of serotonin fibers in the anterior column of the mammalian spinal cord. An immunohistochemical study.

Detailed comparative analysis of the organization of serotonin fibers in the anterior column of the mammalian spinal cord (rat, guinea pig, cat, dog and monkey) was carried out by use of the indirect antibody peroxidase-antiperoxidase (PAP) method. The plexus formation of serotonin-containing varicose fibers around the alpha-motoneurons in the monkey anterior horn was in much closer apposition to the cell bodies in comparison with the spinal cords of the rodents and carnivores. The results may suggest that anterior horn motoneurons in the simian spinal cord are intimately innervated by serotonin fibers in a manner different from that of rodents and carnivores. Furthermore, the small cell groups endowed with particularly dense networks of serotonin fibers were demonstrable in the anterior horn of L1-L2 segments of rats, and L3-L4 of guinea pigs and monkeys; however, in the lumbar levels of the carnivores this was not the case. Hence it seems doubtless that there exists in the lumbar anterior horn of the rodent and primate spinal cords a cell group with an unknown specialized function.

Animals↗
PubMed1983

Immunohistochemical demonstration of serotonin nerve fibers in the neocortex of the monkey (Macaca fuscata).

Using a peroxidase-antiperoxidase immunohistochemical method, the distribution of serotonin nerve fibers was studied in the neocortex of the monkey (Macaca fuscata). All layers of the neocortex showed evidence of serotonin fibers, both fine and thick. Unlike the distribution in rodents, different patterns of distribution were noted in each neocortex of the primate. Among the cortical areas--area 4, 3-1-2, 17, 18, 41 and 42--the primary visual cortex (area 17) contained the highest density of immunoreactive fibers, while the primary motor cortex (area 4) possessed the lowest concentration. The most outstanding finding was a dense and laminar distribution of serotonin fibers in area 17, particularly within the upper portion of layer IVc. In area 3-1-2, 18, 41 and 42, a fairly uniform density of immunoreactive fibers was observed across the six cortical layers, apart from a relatively dense plexus of fine serotonin fibers in layer IV.

Animals↗