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Biomedical subjects

H Maeda

Publications and source records attributed to H Maeda.

At least 667 records · Page 37Linked to original sources
PubMed1993

Bone lesions of multiple myeloma in three dogs.

Three cases of canine multiple myeloma that showed monoclonal IgA gammopathy and bone lesions were examined. One dog was associated with Bence-Jones proteinuria as well. Radiographic examination revealed extensive skeletal involvement of flat bones such as scapula, pelvic bone, costa, and epiphysis of long bones where the hematopoiesis was active throughout the life. Histopathologically, small osteolytic lesions occurred from periosteum and Haversian canal as well as endosteum, and larger lesions were formed by gradual expansion or fusion of small lesions. Osteolytic lesions did not necessarily involve tumor growth, explaining the inconsistent confirmation of tumor cells in biopsy specimens for diagnosis of multiple myeloma and suggesting the possible mechanism for osteolysis by some other humoral factors.

Animals↗
PubMed1993

A tentative classification of "neuroses" based on behavioristic consideration of the pathogenetic mechanisms.

Pathogenetic mechanisms of "neuroses" were reconsidered based on a behavioristic framework which includes not only the traditional stimulus-response learning theory but also the concept of conflict proposed by Lewin. Most of the subtypes of "neuroses"--with the exception of panic disorder--were divided into two categories: conditioned fear-related disorders and conflict-related disorders. Phobias have been suggested to be caused by an escape or avoidance behavior motivated by an unconditioned or conditioned fear and obsessive compulsive disorder by an avoidance behavior motivated by a conditioned fear, while such disorders as posttraumatic disorder or hypochondriasis (nosophobia) were considered to be direct manifestations of conditioned fear. Generalized anxiety and depersonalization disorders were suggested to be caused by conflicts, but these conflicts seemed to persist even after the appearance of the symptoms. In contrast, appearances of conversion, somatization, somatoform pain, psychogenic fugue, or psychogenic amnesia were suggested to result in a temporary attenuation of the causative conflicts.

Anxiety Disorders↗
PubMed1993

Intracranial self-stimulation and locomotor traces as indicators for evaluating the homopantothenic acid.

Our paper compares the effect of homopantothenic acid (HOPA) and haloperidol (HAL), i.e., representative neuroleptics, on intracranial self-stimulation (ICSS) and locomotor activity. These experiments showed that HOPA inhibited abnormal hyperactivity induced by methamphetamine (MAP) but did not inhibit ICSS which is considered with respect to physiological motivations. On the other hand, haloperidol (HAL) markedly inhibited both ICSS and abnormal hyperactivity induced by MAP. We propose that combined ICSS and locomotor traces can be chosen as indicators for evaluation and developing the new neuroleptics.

Animals↗
PubMed1993

Resistance to nitric oxide in Mycobacterium avium complex and its implication in pathogenesis.

Susceptibility of three different strains of Mycobacterium avium complex (MAC), i.e., one strain of M. avium (Mino) and two strains of M. intracellulare (31F093T and KUMS 9007), to nitric oxide (NO) generated by rat alveolar macrophages (M phi) or NO generated chemically by acidification of NO2- was examined in vitro. We also investigated the effects of NO on phagocytosis and superoxide anion (O2-) generation by M phi. The intracellular growth of M. avium Mino was significantly suppressed by NO generated by gamma interferon (IFN-gamma)-stimulated M phi, whereas that of two strains of M. intracellulare (31F093T and KUMS 9007) was not. M. avium Mino was also more susceptible to NO generated chemically by acidification of NO2- than the two M. intracellulare strains. In L-arginine (1 mM)-containing medium, NO release from the M phi assessed by measuring NO2- increased as the concentration of IFN-gamma increased. The enhancing potential of IFN-gamma for NO release became more pronounced when M phi were infected with 31F093T, an NO-resistant strain. A large amount of NO generated by IFN-gamma-stimulated M phi suppressed both phagocytosis and O2- generation by the M phi, especially after infection of the M phi with strain 31F093T. These results indicate that the intracellular growth of MAC is not always inhibited by NO generated by immunologically activated M phi; rather, NO generation induced by infection with an NO-resistant MAC strain suppresses phagocytosis of the M phi, which may allow extracellular spreading of such NO-resistant mycobacteria. Therefore, the pathogenic potential of MAC may be partly attributed to its resistance to NO.

Animals↗
PubMed1993

Pronounced enhancement of .NO-dependent antimicrobial action by an .NO-oxidizing agent, imidazolineoxyl N-oxide.

The antimicrobial action of .NO against Cryptococcus neoformans was investigated by using imidazolineoxyl N-oxide, which we recently reported removes .NO via oxidation (T. Akaike, M. Yoshida, Y. Miyamoto, K. Sato, M. Kohno, K. Sasamoto, K. Miyazaki, S. Ueda, and H. Maeda, Biochemistry 32:827-832, 1993). No appreciable fungicidal activity was observed in neutral .NO solutions. Imidazolineoxyl N-oxide induced or enhanced fungicidal action in neutral or acidic .NO solutions, respectively. Our results provide convincing evidence that .NO is not a microbicidal molecular species.

Anti-Infective Agents↗
PubMed1993

Can brain impairment be detected by in utero behavioural patterns?

Fetal behavioural patterns were examined to test whether they could be used to localise sites of brain damage antenatally. Decreased fetal movement, persistent nonreactive fetal heart rate (FHR) pattern, and/or central nervous system malformation were used as indicators of possible neurological impairment. Ten fetuses tested in this way underwent further ultrasound examination observing movement of the extremities, chest wall (breathing), and eye and mouth, and active/quiet FHR patterns. Eight of these 10 fetuses were found on postnatal examination to have a brain impairment. The fetuses having potential in utero brain impairment were divided into four groups: those with (1) lesion sites at, or caudal to, the pons-medulla that were specifically identified by fetal behaviour, (2) diffuse lesions in the brain which, although resulting in abnormal behaviour, could not be localised by this behaviour, (3) lesions localised in the cerebral hemisphere(s) but with no abnormal behaviour and (4) temporally abnormal behaviour in utero, finally changing over to a normal pattern with no neonatal neurological abnormality. A screening system for the antenatal assessment of brain impairment is thus proposed.

Brain Damage, Chronic↗
PubMed1993

Bladder wall morphology: in vitro MR imaging-histopathologic correlation.

To study the morphology of the normal and inflamed bladder wall, the findings of magnetic resonance imaging and histopathologic examination of 13 in vitro specimens were correlated. Normal bladder wall appeared as a band of intermediate signal intensity on T1-weighted images and as bands of low (inner) and intermediate (outer) signal intensity on T2-weighted images. Inflamed bladder walls demonstrated two additional inner bands of intermediate (inner) and high (innermost) signal intensity on T1-weighted images and high (inner) and low (innermost) signal intensity on T2-weighted images. The mean histopathologic percentages of muscle bundles in inner and outer bands that appeared on T2-weighted images were 92.5% +/- 4.9 and 78.3% +/- 8.2, respectively. The authors conclude that the total thickness of the two bands of differing intensity that appeared on the T2-weighted images of the normal bladder wall correlated well morphometrically with the muscle layers in the histopathologic specimens, and that the different signal intensities in the muscle layer represent a compact inner and looser outer arrangement of smooth muscle bundles.

Aged↗
PubMed1993

Chronic neutropenia associated with C2 and C9 deficiency.

A Japanese male with a deficiency of the second and ninth components of complement associated with chronic idiopathic neutropenia is presented. In this case the second component of complement is totally deficient while the ninth component is approximately half that of normal control. Neutrophil granulocytes are constantly few, but this case shows no evidence of susceptibility to either viral or bacterial infections. His HLA type is different from that of Caucasians, suggesting that the genetic abnormality responsible for the complement deficiency of this Japanese case is different from that seen in Caucasian patients.

Adult↗
PubMed1993

Flat wart of the urethra caused by human papillomavirus type 16.

A rare case of urethral flat wart caused by human papillomavirus (HPV) type 16 was reported. A 34-year-old male consulted our department with a complaint of urethral bleeding. A pair of symmetrical white flat warts combined with ulcer at the urethral meatus were found. Microscopic examination of the specimen demonstrated koilocytosis of the epithelium. In immunohistochemical study it was positive for HPV and HPV type 16 was detected by polymerase chain reaction.

Adult↗
PubMed1993

Reactivity of cerebral blood flow to carbon dioxide in various types of ischemic cerebrovascular disease: evaluation by the transcranial Doppler method.

BACKGROUND AND PURPOSE: The response of cerebral blood flow to changes in the arterial carbon dioxide partial pressure (i.e., carbon dioxide reactivity) has been evaluated as a parameter of cerebral perfusion reserve in patients with cerebrovascular disease. In this study, variations in this reactivity in various ischemic cerebrovascular diseases were evaluated by a newly established method, a transcranial Doppler technique. METHODS: Thirty-three patients with symptomatic cerebrovascular disease, 13 patients with asymptomatic cerebral infarction, and 25 age-matched normal control subjects were investigated. The symptomatic patients were divided into three groups; those with unilateral carotid artery obstruction, those with cortical infarction, and those with lacunar infarction. The carbon dioxide reactivity of each subject was determined by simultaneously measuring the mean spatial Doppler frequency in the middle cerebral artery and the end-tidal carbon dioxide partial pressure under normocapnic, hypercapnic, and hypocapnic conditions. RESULTS: In the patients with carotid obstruction, the carbon dioxide reactivity of the hemisphere ipsilateral to the obstruction was more impaired than the reactivity of the symptomatic hemispheres in any other group, and was significantly less than in the contralateral asymptomatic hemisphere (p < 0.01). In patients with cortical infarction, the carbon dioxide reactivity of the symptomatic hemisphere was significantly less than in normal control subjects (p < 0.05) and was also less than that of the contralateral asymptomatic hemisphere (p < 0.05). In patients with lacunar infarction, the carbon dioxide reactivity of both hemispheres was significantly less than that in normal controls (p < 0.01), although there was no difference between the symptomatic and asymptomatic hemispheres. In patients with asymptomatic infarction, the carbon dioxide reactivity was also less than that in normal controls (p < 0.01). CONCLUSIONS: The carbon dioxide reactivity of cerebral blood flow measured by this transcranial Doppler technique may be useful for characterizing the hemodynamic changes that occur in various types of ischemic cerebrovascular disease.

Brain Ischemia↗
PubMed1993

Rate of successful recording of blood flow signals in the middle cerebral artery using transcranial Doppler sonography.

BACKGROUND AND PURPOSE: To assess the usefulness of transcranial Doppler sonography, we investigated the rate of blood flow signal recording failure in the middle cerebral artery in Japanese subjects. Furthermore, we studied the effect of increased emitted power on the rate of successful recording in some of the patients in whom recording failure had been detected at the standard transducer power of 100 mW/cm2. METHODS: To evaluate the rate of successful recording, we measured blood flow signals in 597 patients (age range, 16 to 89 years) for screening of cerebrovascular disease by using a 2-MHz range-gated, pulsed-wave Doppler instrument at the standard transducer power. In 18 elderly patients with recording failure at the standard power, we assessed the effect of increased emitted power of 400 mW/cm2 on flow signal recording. RESULTS: Blood flow signals were recorded in 920 (77.1%) of the 1194 middle cerebral arteries of the 597 patients studied. The rate of successful recording of bilateral middle cerebral artery flow signals (70.9%; 423 of 597 patients) decreased with age, especially in females (17.0% in women aged 70 years or older). In 12 of 18 elderly patients with recording failure at the standard power, blood flow signals could be detected at the increased emitted power of 400 mW/cm2. CONCLUSIONS: The rate of successful recording of blood flow signals in Japanese subjects decreases with advancing age, especially in females. Increasing the emitted power markedly improves the successful recording rate.

Adolescent↗
PubMed1993

Idiopathic cerebral hemorrhage during delivery in normotensive women--case reports.

Two normotensive pregnant women who developed cerebral hemorrhage during delivery are reported. The hematoma was small and subcortical in one and large and putaminal in the other. They had no history of hypertension, cerebrovascular disorders, or eclampsia. Cerebral angiography studied in one case revealed no abnormalities. Idiopathic cerebral hemorrhage during delivery without any evidence of vascular risk factors is discussed.

Adult↗
PubMed1993

An autopsy case of suicide by hanging with multiple stab wounds of the neck and chest.

We report, from the aspect of 'acting' capability, an autopsy case of suicide by hanging in which multiple deep stab wounds were observed in the neck and chest. A 49-year-old man was found dead in a state typical of hanging. His car was found about 100m away with a blood-stained climber's knife on the seat. Multiple incised and stab wounds were in the neck, with a lesion of the right inner jugular vein. Three penetrating stab wounds of the chest punctured the lungs, with pooling of about 500ml of blood in the left thorax and about 100ml in the right. Two other shallow stab wounds were in the chest. All the above wounds were explainable as self-inflicted. From the autopsy findings and the circumstantial evidence, it was concluded that he walked approximately 100m after stabbing his neck and chest and finally committed suicide by hanging.

Airway Obstruction↗
PubMed1993

Ring fracture of the base of the skull and atlanto-occipital avulsion due to anteroflexion on motorcycle riders in a head-on collision accident.

This report concerns a head-on collision accident of a motorcycle at a very high speed (c. 80-100 Km/h) against a bonnet-type automobile, in which both the motorcyclist and pillion rider were injured at the base of the skull by violent anteroflexion of the head due to the force of inertia. A difference in their injuries was: the motorcyclist sustained a 'ring' fracture and the pillion rider an atlanto-occipital avulsion; dural tear. Anteroflexion without impact on the occiput such as described above seems to be a rare causal mechanism of the 'ring' fracture. In addition, the mode of action of the accelerating forces to the heads of the victims along with their physiques may explain the mechanism which caused the different injuries in this accident.

Accidents, Traffic↗
PubMed1993

Granulomatous leptomeningitis in beagle dogs.

A granulomatous leptomeningitis was seen in seven laboratory Beagle dogs (four males, three females), 14 to 15 months old, that had been used as control or experimental subjects in a toxicologic study. The dogs were clinically normal during the experimental period. Microscopic lesions were characterized by typical noncaseating granulomas in leptomeninges and slight scattered perivascular cuffing in gray and white matter throughout the central nervous system, with no site of predilection. Although no microorganisms could be found by ordinary light microscopic examination, there was a positive reaction for Escherichia coli antigen in the cytoplasm of macrophages, which corresponded to periodic acid-Schiff-positive, calcium-negative, and iron-negative materials in the granulomas and cuffs. Electron microscopic examination revealed that these materials were large phagolysosomes indicative of abnormal lysosomal function. These findings indicate that at least some cases of canine granulomatous leptomeningitis could be very likely caused by E. coli and represent an entity distinct from classical canine granulomatous meningoencephalitis.

Animals↗
PubMed1993

Abnormal behavioral patterns in the human fetus at term: correlation with lesion sites in the central nervous system after birth.

We describe three fetuses at term that demonstrated abnormal behavioral patterns in utero when observed using real-time ultrasound. The abnormal patterns turned out to have neurologic correlations after birth. In case 1, despite a normal breathing pattern, no movement in any of the four extremities was observed, thus suggesting the existence of a spinal cord lesion at the rostral end, located at C4 or C5. In case 2 a lack of breathing movement was noted repeatedly, together with the abnormal finding that alternation of periods of rapid eye movement (REM) sleep with those of non-rapid eye movement (NREM) sleep was not present. These findings implied a lesion involving the pons and/or medulla oblongata. In case 3 movement of the four extremities, breathing movement, and alternating periods of REM sleep and NREM sleep were found to be within the normal range. The concurrence of regular mouthing and the NREM sleep period was not observed, however, suggesting impairment in the brain function responsible for NREM sleep located from the pons through the thalamocortical connection to the cerebral hemisphere.

Adult↗
PubMed1993

Prenatal evaluation and obstetrical management of fetuses at risk of developing lung hypoplasia.

The aim of this study was to measure the fetal lung area of normal human fetuses using ultrasound and them to test the predictive values of a nomogram in the identification of fetal lung hypoplasia. A nomogram for ultrasound-measured fetal lung area were constructed from 264 normal fetuses from 17 to 39 weeks of gestation. In 19 cases running the risk of developing lung hypoplasia, the sensitivity, specificity, and positive and negative predictive values of lung area measurements below the mean -2 SD were 75%, 100%, 94% and 100%, respectively, with total lung area showing a significant relation to the combined lung weight (Y = -1.05 + 2.06 X, r2 = 0.88). These results indicate that lung area measured by ultrasound is a good indicator of lung weight, and this nomogram of lung area may be useful in evaluating lung growth prenatally, as well as in the direct obstetrical management of fetuses at risk of developing lung hypoplasia.

Female↗