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T Hiyoshi

Publications and source records attributed to T Hiyoshi.

At least 37 records · Page 2Linked to original sources
PubMed1991

Human autoantibody to Sertoli cells detected in healthy individuals.

Human autoantibody to Sertoli cells was detected in normal human sera. This IgM-type autoantibody was undetectable during the neonatal period and was found in 11.5% of 365 serum samples taken from adult healthy persons of both sexes. This human autoantibody to Sertoli cells exhibited quite the same target-organ specificity and multi-organ reactivity (salivary gland ductules, pancreatic intercalated duct, renal lower nephron, pituitary acidophilic cells) as those of the murine monoclonal autoantibody (IgM class) to Sertoli cells (TM-1: WHO registered code T43). The TM-1 monoclonal antibody could recognize testicular antigens with molecular weights of 67,000 and 23,000 in Sertoli cells, and had already been demonstrated capable of inducing murine experimental spermatogenic disturbance when administrated together with murine monoclonal autoantibody to seminiferous tubular basement membrane (TM-2: WHO registered code T44). These observations may suggest that human spermatogenic disturbance could be easily induced by the multi-organ reactive autoantibody to Sertoli cells even in healthy individuals under particular conditions where this autoantibody can be allowed to reach the target Sertoli cells across the barrier of seminiferous tubular wall by either autoantibody to seminiferous tubular basement membrane or other toxic damage.

Adolescent↗
PubMed1990

Pyrophosphate-dependent phosphofructokinase. Conservation of protein sequence between the alpha- and beta-subunits and with the ATP-dependent phosphofructokinase.

Full-length cDNA clones for the alpha- and beta-subunits of pyrophosphate-fructose 6-phosphate 1-phosphotransferase have been isolated from a cDNA expression library derived from potato tuber poly(A)+ RNA. The nucleotide sequences indicate that the alpha- and beta-subunits are related with about 40% of amino acid residues being identical. A comparison of the deduced amino acid sequences of both subunits of this enzyme with that of the major ATP-dependent fructose 6-phosphate 1-phosphotransferase from Escherichia coli (Shirakihara, Y., and Evans, P. R. (1988) J. Mol. Biol. 204, 973-994) showed little homology between the proteins except for regions involved in the binding of fructose 6-phosphate/fructose, 1,6-bisphosphate and possibly between regions binding pyrophosphate and the beta- and gamma-phosphates of ADP/ATP. A comparison of the derived secondary structures of the two subunits of the PPi-dependent enzyme with the known secondary structure of the E. coli ATP-dependent enzyme indicated that the overall structure of these enzymes is similar. These data suggest that catalytic activity resides on the beta-subunit of the pyrophosphate-dependent enzyme.

Adenosine Triphosphate↗
PubMed1990

Failure of nine-month phenobarbital administration to reverse amygdaloid-kindled seizure susceptibility in cats.

Upon completion of left amygdaloid kindling, 4 cats underwent long-term phenobarbital administration during the subsequent 5- to 9-month rest period. Plasma phenobarbital levels were maintained above 15 to 20 micrograms/ml and were restimulated following plasma phenobarbital washout. Three cats served as nonmedicated controls. All 7 cats were subjected to repeated 6-hour sleep monitoring for observation of interictal discharges, which were observed most often in the immediate postictal period. Their frequency decreased gradually throughout the experiment in both the medicated and control animals, but they never completely disappeared except from the contralateral amygdala in 1 medicated animal. Upon primary site restimulation, all of the medicated animals responded with a generalized convulsion once the afterdischarge was induced. When these animals underwent secondary-site amygdaloid kindling, 3 showed a positive transfer effect. The findings suggest that although phenobarbital is a potent anticonvulsant, it has little effect on the acquired seizure susceptibility of previously amygdaloid kindled cats.

Amygdala↗
PubMed1990

Surgical treatment of epilepsy in the comprehensive care program: advantages and considerations.

To properly establish the surgical treatment of epilepsy in the comprehensive care program, we planned a surgical strategy mainly for a temporal lobe epilepsy and have performed 60 temporal lobectomies. The surgical candidates were selected from 142 patients who met the initial criteria, and passed the initial evaluation for surgical intervention. Forty-five patients had long-term intracranial EEG recording, and circumscribed organic lesions were disclosed in 27 patients by neuroimaging techniques. The outcome of 23 patients who were followed for 2 years postoperatively was complete freedom from complex partial seizures in 17 patients (74%) and an increase in full employment from 2 to 10 patients. Despite the possible surgical complications, including detrimental effects on the higher cerebral functions, it is essential that the surgical treatment of epilepsy should be established as a part of the comprehensive care program. Our experiences and analyses of the state of the art in surgical intervention also suggest that surgical indications for more intractable patients whose social adjustment is less hopeful should be established and the surgical care system for these patients should also be planned. Furthermore, some patients may be free from recurrent seizures postoperatively, but still have difficulties in social rehabilitation. The problems for such patients remain unsolved.

Adult↗
PubMed1990

Subtypes of temporal lobe epilepsies: a clinical point of view.

We studied 40 patients with temporal lobe epilepsies who had long-term intracranial EEG recordings and temporal lobectomies. They were divided into 3 groups on the basis of the anatomical site of seizure origin. An electrode implantation technique combined intracerebral depth electrodes with subdural strip electrodes. The seizures were of amygdalo-hippocampal origin in 18 patients, lateral temporal in 13 patients, and temporo-basal in 9 patients. The clinical and EEG features were reviewed retrospectively with regard to 3 factors in each patient: localization of interictal spikes in the scalp-recorded EEG, signal symptoms (auras), and presumed etiologies. Epilepsy with amygdalo-hippocampal and lateral temporal seizures was found to be distinguishable by the electroclinical features. It seems practical to classify these 2 subtypes of temporal lobe epilepsies as in the 1989 Classification of Epilepsies and Epileptic Syndromes. Temporal lobe epilepsies thus defined can be regarded as epileptic syndromes rather than a cluster of seizure manifestations.

Adolescent↗
PubMed1990

Feasibility of subclassification of temporal lobe epilepsy (1989): an etiological overview.

Temporal lobe epilepsy with amygdalohippocampal seizures may have episodes of severe convulsions in childhood more frequently and the onset age is significantly lower compared to epilepsy with lateral temporal seizures. To the contrary, tumorous lesions are found more frequently in epilepsy with lateral temporal seizures. In view of the presumed known etiologies in relation to the localization of epileptogenic foci, the Classification of Epileptic Syndrome (1989), subdividing temporal lobe epilepsies into 2 groups, was found to be useful.

Adult↗
PubMed1989

Feline amygdaloid kindling and sleep.

Six hourly polygraphic examinations of sleep organization were made before and after amygdaloid (AM) kindling in 7 cats. After completion of AM kindling and the repetitive induction of kindled convulsion, the percentage of time spent in rapid eye movement sleep (REMS) significantly decreased, although the animals began to spend significantly more time in sleep. This altered sleep pattern persisted during an extended 22.5 h recording in 2 cats. The decreased waking (W) and REMS, as well as the increased slow wave sleep (SWS), appeared to be due to changes in mean duration but not in the total number of periods. Suppression of REMS but not SWS was also manifested as a delayed onset of REMS following sleep onset, the latency of which remained constant upon placement of animals in the recording chamber. These changes in sleep organization were transient, however, as they returned completely to the baseline pre-kindling level after a rest interval of 3-4 weeks without kindling stimulation. It is concluded that sleep organization changes, particularly those characterized by the suppression of REMS, are independent of the acquisition of AM-kindled seizure susceptibility; rather they are the direct correlates of generalized convulsion itself.

Amygdala↗
PubMed1989

Emotional facial expressions at the onset of temporal lobe seizures: observations on scalp and intracranial EEG recordings.

The initial facial expressions of 195 complex partial seizures of 98 patients with temporal lobe epilepsy were reviewed in relation to the laterality and focality of electroencephalographic (EEG) seizure origin. A neutral expression was observed most often (71) followed in frequency by expressions of disgust (13), happiness (7) and sadness (7). There was no expression of anger, surprise and fear. No correlation was found between the type of facial expression and the side of seizure origin. However, among 27 patients examined by means of intracranial EEG recordings, it was evident that a disgust expression occurred with oro-alimentary automatisms at the beginning of mesial temporal lobe seizures, whereas a happy one occurred without oro-alimentary automatisms at the beginning of lateral temporal lobe seizures. Although the facial expressions were not always related to the concurrent ictal emotion, it appeared that the majority of the patients with the disgust expression had autonomic features, while those of the happy/sad expression had psychic/sensory ones. It was concluded that (1) a disgust expression occurs as an indirect consequence of "crude sensation," while a happy/sad expression occurs as a direct consequence of "elaborate mental state" (Jackson) and (2) facial expressions must be reviewed in relation to focality rather than laterality in temporal lobe seizures.

Adolescent↗
PubMed1989

Focal lymphocytic infiltration in the adrenal cortex of the elderly: immunohistological analysis of infiltrating lymphocytes.

The incidence of mononuclear cell infiltration in the adrenal cortex was examined in autopsy cases of young and old subjects, and the infiltrating mononuclear cells were immunohistologically characterized by monoclonal antibodies. Histologically, 110 of 174 autopsy cases of persons greater than 60 years (63.2%) were shown to have mononuclear cell infiltration of varying degree within the adrenal cortex, whereas such a lesion was observed in lesser incidence (7.4%) in the 54 younger, control subjects aged less than 49 years. In addition, severely infiltrating lesions in the adrenal cortex were found frequently in the elderly greater than 70 years. Immunohistochemical study revealed that the infiltrating mononuclear cells were mainly composed of CD3+ T cells. The major proportion of CD3+ T cells expressed CD4, whereas CD8+ T cells were less in number. Moreover, a considerable proportion of CD4+ T cells was activated as judged by interleukin 2 receptor expression. These findings indicate that T lymphocytes infiltration in aged human adrenal cortex may represent a pre-clinical manifestation of organ-specific autoimmune adrenalitis which is based on autoimmunity associated with ageing process.

Adrenal Cortex↗
PubMed1988

Midline thalamic lesion and feline amygdaloid kindling. I. Effect of lesion placement prior to kindling.

Nine cats with electrolytic lesion in the massa intermedia (MI, N = 8) and ipsilateral nucleus centrum medianum (CM, N = 1) underwent primary and secondary site amygdaloid (AM) kindling and primary site retest. During primary site kindling, MI- but not CM-lesioned animals showed a pattern of seizure development strikingly similar to that of forebrain-bisected cats and the development of contralateral hemiconvulsive seizure was coincident with the onset of afterdischarge (AD) in the ipsilateral motor cortex. Unlike the forebrain-bisected ones, the MI-lesioned animals eventually developed bisymmetrical clonic convulsion with initial contralateral and then ipsilateral clonic involvement. At the secondary site, no positive transfer effect was noted in 1 CM-lesioned and 6/7 MI-lesioned cats. When the primary site was retested, a marked interference effect was observed. The lesion site responsible for these unique kindling features was in the rostral half of the MI with varying involvement of the nucleus centralis medialis (NCM). It is concluded that the MI plays an important role both for transhemispheric ictal propagation and for positive transfer effect in feline AM kindling. However, the mechanisms underlying these two phenomenon are unlikely to be the same since these effects can be totally divorced.

Amygdala↗
PubMed1988

Midline thalamic lesion and feline amygdaloid kindling. II. Effect of lesion placement upon completion of primary site kindling.

Lesion placement in the massa intermedia (MI) prior to amygdaloid (AM) kindling distinctively modifies the pattern of transhemispheric ictal transmission to one similar to that of forebrain-bisected cats, and eliminates the positive transfer effect (Hiyoshi and Wada 1988). Since the mechanism of AM seizure development is not the same as that for maintenance of AM-kindled seizure susceptibility, the effect of MI lesioning on established primary site AM-kindled seizures and secondary site AM kindling was studied in 8 cats. Upon the first primary site AM restimulation following MI lesioning, all animals responded with established bisymmetrical generalized tonic-clonic convulsions. Subsequent secondary site AM kindling showed (1) a distinctively modified seizure pattern identical to that observed during primary site kindling in cats with 'prior-to-kindling' MI lesions, and (2) complete absence of positive transfer effects. At primary site retest, the animals again responded with an established bisymmetrical convulsion and a marked interference effect (negative aftereffect) was noted. It is concluded that (1) the positive transfer effect at the contralateral homotopic AM is primary site hemisphere dependent, (2) the MI is critically involved in this effect, (3) the MI is not critical for maintaining the bisymmetrical pattern of AM-kindled convulsions, and (4) the mechanisms underlying the transhemispheric positive and negative transfer effects are different.

Action Potentials↗
PubMedDate not supplied

Anticonvulsive effect of dapsone (4,4'-diaminodiphenyl sulfone) on amygdala-kindled seizures in rats and cats.

Dapsone (4,4'-diaminodiphenyl sulfone; DDS), an established anti-leprosy drug, showed anticonvulsive effects in the amygdaloid kindling model of epilepsy. Single doses of the drug in rats (6.25-12.5 mg/kg, i.p.) suppressed the kindled seizures in a dose-dependent manner without overt behavioral toxicity. With repeated oral administration in cats, relatively higher initial doses (13-23 mg/kg) were required to obtain seizure suppression, and neurotoxic signs occurred within a few days with serum drug levels of approximately 20 micrograms/ml. Although dapsone showed anticonvulsive effects in both animal species, the effective serum levels overlapped the toxic levels reported in the clinical treatment of leprosy. In the majority of the cats, however, seizure suppression was maintained even after the discontinuation of dapsone with lower serum levels than those observed at the beginning of the seizure suppression. Therefore, dapsone would be useful as an antiepileptic drug only when long-term anticonvulsive efficacy is demonstrated using smaller doses comparable to those used in the treatment of leprosy.

Amygdala↗
PubMedDate not supplied

Surface roughness of cellulose hollow fiber dialysis membranes and platelet adhesion.

A great deal of research has been conducted focusing on membrane materials with reference to their blood compatibility, but blood compatibility is influenced both by the material used in membranes and their structure, and by the flow conditions at the membrane surface. Accordingly, the relationship between membrane surface roughness and hemocompatibility has been evaluated using five types of membranes of differing surface roughness by evaluating the inner surfaces of the hollow fibers by atomic force microscopy (AFM) and by measuring platelet adhesion ratios using bovine blood. The yield stress, which equates to flow characteristics, was also evaluated using a glycerol suspension of polymethylmethacrylate (PMMA), a Bingham fluid. It was found that membranes having rough surfaces had high platelet adhesion ratios and poor hemocompatibility, whereas those with smoother surfaces had lower platelet adhesion ratios and better hemocompatibility. Measurement of the yield stresses for these membranes revealed higher values for those with rough surfaces, and lower values for those with smoother polyethylene glycol (PEG) grafted surfaces. This suggests that flow conditions at the membrane surface differ according to its surface roughness, and that this difference in flow conditions also influences hemocompatibility.

Cellulose↗
PubMedDate not supplied

Feline agenesis of the corpus callosum.

The unusual pattern of seizure development and developed seizure in a cat kindled at the ventral hippocampus is discussed in the light of agenesis of the corpus callosum (CC). In this animal, not only the CC but also the hippocampal commissure was completely absent and the dorsal portion of the septal area was separated in the midline. There was no other morphological anomaly except for slightly enlarged lateral ventricles. No behavioral or physical peculiarities were noted. The unusual profile of kindling in this animal was characterized by (a) very rapid kindling at the primary site, (b) the lateralized nature of the kindled primary site convulsion preceded by repetitive and violent contralateral axial rotation, and (c) the complete absence of positive transfer effect expected at the contralateral homotopic secondary site. These features are strikingly reminiscent of the pattern of amygdaloid kindling in forebrain-bisected cats. These observations add strength to our hypothesis that the CC (and possibly the hippocampal commissure) is the major anatomic substratum for convulsive generalization and the transhemispheric positive transfer effect in feline limbic kindling.

Agenesis of Corpus Callosum↗
PubMedDate not supplied

Centrally induced feline emotional behavior and limbic kindling.

The threshold intensity required for electrical hypothalamic/mesencephalic stimulation to elicit emotional behavior in cats was examined chronologically during limbic kindling (n = 9/5), and without kindling (n = 3/3) for a matching control period. After the completion of primary site amygdaloid (AM) or hippocampal (HIPP) kindling, the hypothalamic defensive behavior threshold showed a +/- 20% fluctuation from the prekindling baseline with a mean tendency for reduction as in the control animals. The flight behavior threshold increased in the kindled animals, and decreased in the controls; however, the degree of change was not statistically significant. In contrast, the mesencephalic defensive behavior threshold, which was quite stable in the controls, decreased significantly upon primary (mean -13.5%) and secondary site (mean -22.2%) AM kindling, whereas the flight and screeching (sound emission) behavior threshold remained unchanged throughout kindling. The decreased or unchanged thresholds for each behavior were independent of the timing of the hypothalamic/mesencephalic stimulation after kindled generalized convulsion. The decreased mesencephalic defensive behavior threshold persisted during a 1- to 3-month rest period without kindling stimulation. These findings suggest that acquisition of feline AM-kindled seizure susceptibility is associated with a lasting facilitation of midbrain (but not hypothalamic) excitability for defensive (but not flight) behavior.

Animals↗