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T Nara

Publications and source records attributed to T Nara.

At least 73 records · Page 4Linked to original sources
PubMed1994

Development of the human medial superior olivary nucleus: a morphometric study.

The development of the human medial superior olivary nucleus was studied in serial sections of 10 fetuses at 12-35 weeks of gestation (WG), an infant at 2 months of age and an adult of 63 years using an electronic planimeter with a computer. Morphometric analysis suggested that the development of the human medial superior olivary nucleus accelerates between 16 and 21 WG in terms of columnar lengths and volumes, neuronal sizes and circularity ratios, while it matures gradually in terms of the amount of Nissl bodies.

Female↗
PubMed1994

Demonstration of the target molecule of a protective IgE antibody in secretory glands of Schistosoma japonicum larvae.

We have demonstrated that a mouse monoclonal IgE antibody, SJ18 epsilon.1, recognizes a 97 kDa surface molecule (Sj97) of Schistosoma japonicum larvae and that the antibody induces partial but significant protection against the skin to lung-stage of S. japonicum infection. The antibody stimulates eosinophil- and macrophage-mediated killing of schistosomula in vitro. In the present study, we isolated the putative full-length cDNA of Sj97 by screening a lambda gt11 cDNA library from S. japonicum adult worms with SJ18 epsilon.1. The predicted amino acid sequence of the cDNA showed highly significant homology to that of S. mansoni paramyosin, a potential vaccine candidate for schistosomiasis. The deletion mutants of S. japonicum paramyosin were expressed in Escherichia coli and the translation product of 443 amino acid residues of paramyosin was found to be recognized by the antibody. Moreover, we observed by immunoelectron microscopy the presence of paramyosin in the post-acetabular gland as well as in the tegument and muscle layers of the larvae. These results suggest that paramyosin is a secretory protein which may be incorporated into the tegument during the development of schistosomula, thus becoming a target for protective immunity during the migratory phase of the parasite.

Amino Acid Sequence↗
PubMed1994

[A case of hemimegalencephaly: ictal EEG and SPECT].

A case of 1-month-old female infant with hemimegalencephaly was reported. This disorder is a rare malformation characterized by congenital hypertrophy of one hemisphere and ipsilateral ventriculomegaly. Clinical signs of the patient included a left sided macrocephaly, intractable seizures and delayed development. Ictal single photon emission computed tomography (SPECT) on the 49th day using 99mTc-HMPAO showed hyperperfusion in the left occipital and frontal lobes, when ictal EEG showed a sharp wave-burst appearing continuously in the left occipital lobe that spread to the left frontal lobe. Interictal SPECT on the 48th day demonstrated and increased tracer accumulation in the left hemisphere, especially in the left frontal lobe. In this case, the megalencephalic hemisphere might have an important role for epileptogenesis and its spread according to the ictal SPECT findings.

Brain↗
PubMed1994

[Brain perfusion in acute infantile hemiplegia studied with single photon emission computed tomography].

Sequential examinations of single photon emission computed tomography (SPECT) were performed on a 5-month-old boy with acute infantile hemiplegia from the acute ictal stage. SPECT was performed with technetium-99m-hexamethyl-propylene-amineoxime during the status when the patient had left-hemiconvulsions (status epilepticus) and on the 3rd, 7th and 10th day after the status. During the ictal stage and the 3rd day after the status, diffuse hyperperfusion was revealed in the right hemisphere, while diffuse hypoperfusion was exhibited in the right hemisphere on the 7th and 10th day after the status. Hypoperfusion in the corresponding hemisphere, after the status, has been reported in patients with acute infantile hemiplegia. There has, however, been no report of ictal brain perfusion. The pathogenesis of this hyperperfusion is not clear, but alteration of brain perfusion in this patient, especially in acute phase, may help to elucidate the etiology of acute infantile hemiplegia.

Brain↗
PubMed1993

Morphometric development of the human auditory system: ventral cochlear nucleus.

The development of the human cochlear nucleus was studied in serial sections of the brain of 12 fetuses at 12-40 weeks of gestation, an infant at 2 months of age and an adult of 63 years using an electronic planimeter with a computer. Morphometric analysis of the development of the ventral cochlear nucleus showed that its development accelerates after 18 weeks of gestation in terms of columnar volume, columnar length, neuronal number and neuronal size.

Auditory Pathways↗
PubMed1993

Neurological manifestations of hemorrhagic colitis in the outbreak of Escherichia coli O157:H7 infection in Japan.

An outbreak of hemorrhagic colitis associated with Escherichia coli O157:H7 occurred in a kindergarten in Saitama, Japan from September to November, 1990. Seven patients admitted to our hospital showed neurological manifestations: generalized seizures, impaired consciousness, urinary incontinence, gaze nystagmus, phrenic nerve palsy, action tremor and vertigo. Two patients died. On the basis of the clinical courses and laboratory findings of the seven patients and postmortem findings of one case, these neurological symptoms were suspected to be induced by the verotoxin elaborated by Escherichia coli O157:H7.

Bacterial Toxins↗
PubMed1992

Development of the human pontine nuclei: a morphometric study.

The morphometric development of the pontine nuclei in the human fetus from 16 to 40 gestational weeks, in a 2-month-old infant and in a 63-year-old adult were examined employing a serial celloidin section method and computer assisted electronic planimeter. The results of our study can be summarized as follows: (1) the development of the human pontine nuclei accelerated in volume after 32 gestational weeks and continued after birth, (2) neuron numbers remained relatively constant after 27 gestational weeks. It was difficult to clearly distinguish neurons from glia before 27 gestational weeks. The total estimated neuronal numbers were not indicative of the gestational stages in infants 27 gestational weeks and older, (3) individual neurons appeared to continue to develop after 32 gestational weeks in accordance with size, distribution and circularity ratio, (4) many islet-shaped groups of large neurons appeared and were scattered throughout the pontine nuclei after 32 gestational weeks.

Cell Count↗
PubMed1992

[Development of human cerebellar granular layer: a morphometric study].

Development of the cerebellar granular layer, the external granular layer (EGL) and the internal granular layer (IGL), was studied morphologically to make complete serial sections of the brain from human fetuses ranging 12 to 40 weeks' gestation (WG). To examine the chronological changes and the regional differences, we measured the thickness of the layer microscopically among five different parts of the cerebellum: anterior lobe/hemisphere (AH), anterior lobe/vermis (AV), posterior lobe/hemisphere (PH), posterior lobe/vermis (PV) and flocculus (FL). EGL was the most superficial layer composed of densely packed undifferentiated cells. Its thickness showed little changes during the fetal period of 12-40 WG for all parts except FL where EGL was thicker than those in other parts and made a gradual attenuation with development. We noticed at least three stages in the fetal development of IGL: 1) the primary or undifferentiated stage (before 18 WG) when IGL was hardly distinguishable from the layer of immature Purkinje cells (PCL); 2) the secondary or intermediate stage (18 to 30 or 35 WG) when it was clearly visible and almost stable in thickness for all parts; 3) the tertiary or developing stage (30 or 35 to 40 WG) when it showed a dramatic increase in thickness as the formation of cerebellar folia was proceeding. During the intermediate stage the Lamina dissecans was observed between PCL and IGL typically in PH. Regional differences were detected in a period of transition from the intermediate to the developing stage among each part: the developing stage appeared earliest in AV and FL and latest in PH.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebellum↗
PubMed1992

[Neurological manifestations in hemorrhagic colitis associated with Escherichia coli O 157: H 7].

From September through November 1990, an outbreak of hemorrhagic colitis associated with Escherichia coli O 157: H 7, occurred in a kindergarten in Saitama, Japan. Some of the patients suffered from neurological symptoms such as stupor, deep coma and/or convulsions in the acute stage, and/or action tremors, nystagmus, incontinence, phrenic nerve palsy in the later stage. Serum complements decreased more in the patients with neurological symptoms than in the patients without them. The verotoxin elaborated by E. coli O 157: H 7 was considered to cause the neurological symptoms, on the basis of their clinical courses and laboratory findings, especially the cerebrospinal fluid findings.

Child↗
PubMed1991

Development of the human dorsal nucleus of vagus nerve: a morphometric study.

The development of the human dorsal nucleus of the vagus nerve was studied on serial sections of the brain of 10 fetuses at 16-40 weeks of gestation, an infant at 2 months of age and an adult of 63 years. A morphometric analysis revealed that the nucleus is divided into three subnuclei (caudal, dorsal and ventral) and that this subdivision is maintained from 16 weeks of gestation to adulthood. The early development of the nucleus is gradual between 16 and 40 weeks of gestation without the rapid growth phase apparent with the motor trigeminal, hypoglossal and facial nuclei.

Brain↗
PubMed1991

Existence of host-related DNA sequences in the schistosome genome.

DNA sequences homologous to the mouse intracisternal A particle and endogenous type C retrovirus were detected in the DNAs of Schistosoma japonicum adults and S. mansoni eggs. Furthermore, other kinds of repetitive sequences in the host genome such as mouse type 1 Alu sequence (B1), mouse type 2 Alu sequence (B2) and mo-2 sequence, a mouse mini-satellite, were also detected in the DNAs from adults and eggs of S. japonicum and eggs of S. mansoni. Almost all of the sequences described above were absent in the DNAs of S. mansoni adults. The DNA fingerprints of schistosomes, using the mo-2 sequence, were indistinguishable from each other and resembled those of their murine hosts. Moreover, the mo-2 sequence was hypermethylated in the DNAs of schistosomes and its amount was variable in them. These facts indicate that host-related sequences are actually present in schistosomes and that the mo-2 repetitive sequence exists probably in extra-chromosome.

Animals↗
PubMed1991

Thermosensing ability of Trg and Tap chemoreceptors in Escherichia coli.

The thermosensing ability of the Trg and Tap chemoreceptors in Escherichia coli was investigated after amplifying these receptors in a host strain lacking all four known chemoreceptors (Tar, Tsr, Trg, and Tap). Cells with an increased amount of either Trg or Tap showed mostly smooth swimming and no response to thermal stimuli. However, when the smooth-swimming bias of the cells was reduced by adding Trg- or Tap-mediated repellents, the cells showed clear changes in the swimming pattern upon temperature changes; Trg-containing cells showed tumbling at 23 degrees C but mostly smooth swimming at 32 degrees C, while Tap-containing cells showed smooth swimming at 20 degrees C but tumbling at 32 degrees C. These results indicate that although both Trg and Tap have the ability to sense thermal stimuli, Trg functions as a warm receptor, as reported previously for Tar and Tsr, while Tap functions as a cold receptor.

Bacterial Proteins↗
PubMed1991

Experience of surgical treatment for craniofrontonasal dysplasia.

We present a case of a 5-year-old girl diagnosed as having craniofrontonasal dysplasia (CFND), which was first reported by Cohen in 1979. CFND is very rare and reports concerning this syndrome have never been found in Japan. In our case, frontal plagiocephaly, third degree orbital hypertelorism and clefting nasal tip coexisted. At 10 months after birth when she visited our hospital, signs of craniostenosis were not recognized and cosmetic improvement was considered the main purpose of the treatment. We performed supraorbital bar reshaping, ethmoidectomy and orbitotomy for reconstruction in one-stage at the age of five. The operation produced marked improvement in her exotropia before entering a primary school. Past reports dealing with abnormalities of the central nervous system in this syndrome are few, but agenesis of the splenium was noted in our case. This paper is a report of our findings together with some discussions in reference to the literature.

Child, Preschool↗
PubMed1991

Serologic and ultrasonographic parameters of praziquantel treatment of hepatic fibrosis in Schistosoma japonicum infection.

We describe the parameters useful in evaluating the development of hepatic fibrosis in Schistosoma japonicum infection, as well as its improvement after treatment with praziquantel (PZQ). Various serologic parameters and ultrasonographic images were examined, and their changes were monitored using rabbits infected with 200 or 300 cercariae of S. japonicum. Infected rabbits were administered one oral treatment of PZQ at a dosage of 100 mg/kg at 6, 12, or 24 weeks after infection. Histopathologic examinations revealed that PZQ had a strong and rapid effect, even on damage that developed long after the infection. The improvement of moderate hepatic fibrosis that developed over 24 weeks after infection was also detected by histopathologic examinations. The serum level of total bile acid was the most sensitive parameter in evaluating the severity of hepatic fibrosis and its improvement after treatment with PZQ. The level of serum procollagen-III-peptide was also useful in evaluating the development of hepatic fibrosis, but not in its improvement. Ultrasonography revealed specific echogenic bands and nodules according to the progress of granuloma formation and fibrosis, and the reversal of these changes could also be observed after treatment with PZQ.

Alanine Transaminase↗
PubMed1991

[Crossed cerebellar diaschisis demonstrated by SPECT in hemiplegic children].

Crossed cerebellar diaschisis (CCD) in twenty five children with hemiplegia were studied using single photon emission computed tomography (SPECT) with N-isopropyl-p-I-123-iodoamphetamine. Seven of twenty-five patients had cerebral palsy, and the others were impaired by acquired brain injury between ten months and fourteen years of age. CCD was demonstrated in five patients (20%), who were impaired by acquired brain injury after seven years of age. CCD could never be detected in patients with cerebral palsy. Ipsilateral cerebellar diaschisis was also demonstrated in two patients with cerebral palsy and three with early acquired brain injury before three years of age. It is suggested that diaschisis presents itself as a different form in a contralateral and ipsilateral cerebellum before three years of age from a form which presents after seven years of age.

Adolescent↗
PubMed1991

[A case of acute polyradiculoneuritis associated with autonomic involvement of the pupils].

Acute polyradiculoneuritis relapses rarely, and autonomic nerve involvement is less frequent than motor cranial nerve involvement. An 11-year-old boy exhibited acute relapsing polyradiculoneuritis associated with two types of autonomic dysfunction of pupils 6 months after the onset of the disease. Parasympathetic dysfunction of pupils with ocular palsies preceded neuropathy of limbs at the onset. Thereafter, sympathetic dysfunction of pupils without ocular palsies was revealed by pupillography at the 2nd attack of limb palsies.

Autonomic Nervous System Diseases↗
PubMed1990

Dynamic changes of DNA sequences in Schistosoma mansoni in the course of development.

Deletion and/or amplification of DNA sequences in Schistosoma mansoni were demonstrated by Southern blot analysis. Total cellular DNAs and genomic clones derived from S. mansoni miracidia, adult males and females were used as probes. Endonuclease BamHI-restricted DNAs from miracidia, adult males and females of both S. mansoni and S. japonicum were reacted to each probe. Hybridization with a total cellular DNA from S. mansoni miracidia as a probe showed elimination of signals in S. mansoni adults. On the other hand, blot analysis using a total cellular DNA from S. mansoni adult males as a probe revealed elimination of hybridization signals in S. mansoni miracidia. Hybridization with a clone SmE15 DNA from S. mansoni miracidia as a probe showed no signal in the DNAs from S. mansoni adults, indicating these sequences deleted in adults. Hybridization experiments using the probes SmF25 and SmM51 which are 1.3 and 2.2 kb fragments cloned from S. mansoni adult females and males respectively, demonstrated no signal to DNA from S. mansoni miracidia. Our data suggested the existence of stage-specific DNA sequences in S. mansoni. We propose a model for multiple-step rearrangement of DNA sequences in S. mansoni during the course of development.

Animals↗