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Biomedical subjects

T Takasu

Publications and source records attributed to T Takasu.

At least 73 records · Page 4Linked to original sources
PubMed1996

Effects of intravenous L-dopa on P300 and regional cerebral blood flow in parkinsonism.

The P300 and regional cerebral blood flow were measured before and after intravenous injection of L-dopa in 10 patients with idiopathic Parkinson's disease and 10 patients with vascular parkinsonism. The P300 was measured with an evoked potential recorder using an oddball paradigm and the regional cerebral blood flow was measured using the stable xenon computed tomography method. The P300 latency was significantly longer and the regional cerebral blood flow in the cerebral cortex and basal ganglia was significantly lower in the Parkinson's disease group and the vascular parkinsonism group than in the age-matched healthy control group. The intravenous injection of L-dopa improved these abnormalities significantly in the Parkinson's disease group but did not improve these abnormalities in the vascular parkinsonism group. Cognitive function is considered to be impaired in Parkinson's disease and vascular parkinsonism and L-dopa is considered to improve it in Parkinson's disease.

Aged↗
PubMed1995

Effects of chemical stimulation of the rostral and caudal ventrolateral medulla on cerebral and renal microcirculation in rats.

We investigated the effects of neurons in the rostral and caudal ventrolateral medulla (RVL and CVL) on cerebral and renal microcirculation in rats. Rats were anesthetized with chloralose, paralyzed with tubocurarine, and artificially ventilated. Cerebral and renal blood flows (CBF and RBF) were measured simultaneously using laser-Doppler flowmetry. Chemical stimulation of the RVL neurons by microinjection of the excitatory amino acid L-glutamate increased arterial pressure (AP), whereas that of the CVL neurons decreased AP. Stimulation of the RVL neurons also elicited a stimulus-locked increase in CBF and a decrease in RBF. The percent change in CBF and RBF was dose-dependent as stimulus intensity was increased. Cerebral and renal vascular resistance (CVR and RVR) levels were calculated from changes in CBF or RBF and changes in mean AP. The percent reduction in CVR and percent elevation in RVR were also dose-dependent. Chemical stimulation of the CVL neurons elicited a stimulus-locked decrease in CBF and an increase in RBF. The percent reduction in CBF and percent elevation in CVR were dose-dependent. The percent reduction in RVR was also dose-dependent, while the percent elevation in RBF was not significant. Blood withdrawal reduced AP by a similar degree to CVL stimulation, but did not significantly decrease CBF. The results suggest that RVL and CVL neurons integrate cerebral and systemic microcirculation.

Animals↗
PubMed1995

Amyotrophic lateral sclerosis with marked neurological asymmetry: clinicopathological study.

We attempted to correlate the marked neurological asymmetry observed in two amyotrophic lateral sclerosis patients with their histopathological lesions. Patient 1, a 52-year-old man, developed dysarthria and dysphagia, followed by muscle weakness in the left arm and then of the left leg. Patient 2, a 44-year-old man, developed muscle weakness in the left hand, left leg, tongue with left-sided predominance, right hand and right leg in that order of progression. Both patients exhibited moderate to marked left-sided predominant involvement of the lower motor neuron system, accompanied by retained or hyperactive deep tendon reflexes on the left side in the early stage of their illness. Most of the asymmetry in the lower motor neuron system involvement persisted until the death of the patients. Histopathological examinations, including semiquantitative analysis, revealed that both patients exhibited left-sided predominant degeneration of the lower motor neuron system at those spinal cord levels where the neurological asymmetry was of a moderate to marked degree. In addition left-sided predominant degeneration of the lateral corticospinal tracts was seen in both patients and right-sided predominant involvement of Betz cells in the leg area of the motor cortex of patient 1. This pattern of both the neurological and histopathological asymmetry suggested the probable existence of an intimate somatotopically related linkage between the upper motor neuron system degeneration and lower motor neuron system degeneration in both patients.

Amyotrophic Lateral Sclerosis↗
PubMed1995

Contingent negative variation and movement-related cortical potentials in parkinsonism.

The contingent negative variation (CNV) and movement-related cortical potentials (MRCPs) were recorded in 10 cases of Parkinson's disease, 10 cases of vascular parkinsonism and 10 age-matched healthy controls. The amplitude of the early CNV was smaller in the Parkinson's disease group and the vascular parkinsonism group than in the healthy control group. The latencies of Bereitschaftspotential (BP) and negative slope (NS') were longer and the amplitude of BP was smaller in the Parkinson's disease group and the vascular parkinsonism group than in the healthy control group. These abnormalities in CNV and MRCPs were improved by intravenous injection of L-DOPA.

Aged↗
PubMed1995

Human T-lymphotropic virus type I associated myelopathy treated effectively with lymphocytapheresis using a leukocyte removal filter.

The patient, a 61-year-old woman, received a blood transfusion at the age of 33 years. Weakness of the lower extremities developed at the age of 42 and the diagnosis of human T-lymphotropic virus type I (HTLV-I) associated myelopathy was made. Somatosensory evoked potential examination showed that the latency of P27 evoked by peroneal nerve stimulation was 44 msec. Lymphocytapheresis was performed 3 times with one-week intervals using a leukocyte removal filter. The muscle weakness began to improve on the second day after the second lymphocytapheresis and the sensory impairment began to improve on the third day after the third lymphocytapheresis. The delayed latency of P27 improved after the lymphocytapheresis. The effectiveness of lymphocytapheresis in this case suggests that lymphocytes are involved in the pathogenesis of HTLV-I associated myelopathy.

Evoked Potentials, Somatosensory↗
PubMed1995

[Cerebral blood flow increase and P300 latency prolongation by intravenous injection of acetazolamide--investigation in lacunar cerebral infarction and healthy subjects].

The cerebral blood flow and the P300 were measured before and 20 minutes after intravenous injection of 17 mg/kg acetazolamide in 15 cases of lacunar cerebral infarction and 10 healthy subjects. In cerebral infarction, the study was performed within 2 weeks after the onset. The cerebral blood flow except the infarcted area was increased significantly by the intravenous injection of acetazolamide in the lacunar cerebral infarction group and the healthy subject group. The blood flow decrease around the infarcted area (intracerebral steal phenomenon) by the intravenous injection of acetazolamide was not observed in any case. The N200 latency and the P300 latency were prolonged significantly by the intravenous injection of acetazolamide in the lacunar cerebral infarction group and in the healthy subject group but the N100 latency and the P200 latency did not show any significant changes. Despite the increase in cerebral blood flow, cerebral function may be decreased by intravenous injection of acetazolamide.

Acetazolamide↗
PubMed1995

[A case of variant Gerstmann-Sträussler-Scheinker disease with the mutation of codon P105L].

Here we present a case of variant GSS disease with mutations in codons 1055 and 129 in a prion protein. The patient was a 54-year-old male, who developed weakness in the lower limbs and spastic, wide-based gait at the age of 46 years. Subsequently he developed dementia and spastic quadriplegia at the age of 49. He had marked pseudobulbar palsy at the age of 50 and became bed-ridden in decorticated posture at teh age of 53. CT and MRI examinations revealed marked atrophy of the frontal and temporal lobes, but the occipital lobes and the cerebellum were spared. His sister had been reported by Amano, et al. in 1992 as a case of variant GSS syndrome, who had very similar clinical features, and had numerous prion protein positive plaques in her cerebral cortex at the time of autopsy. His sister was confirmed to have the same mutations in a prion protein as the present case in later genetic studies.

Atrophy↗
PubMed1994

Inhibitory effects of botulinum toxin on 5-HT1C receptor-induced Cl- current in Xenopus oocytes.

Several low molecular weight G proteins have been identified, but their functional roles remain unclear. To clarify the involvement of low molecular weight G protein in receptor-stimulated turnover of polyphosphoinositide (PI) turnover, influences of botulinum toxins on serotonin (5-HT)-stimulated Cl- current mediated by PI turnover were investigated using Xenopus oocytes injected with rat brain mRNA. Treatment with botulinum toxin C, D or purified ADP-ribosyltransferase of botulinum toxin (botulinum toxin C3 enzyme) inhibited the 5-HT-induced Cl- current in oocytes, and ADP-ribosylated 23 kDa proteins. Both botulinum toxin C3 enzyme-induced inhibition of the current and ADP-ribosylation were suppressed by pretreatment with antibotulinum toxin C3 enzyme antibody. Botulinum toxin D treatment of oocytes was ineffective in the response of Cl- current induced by injection of 50 pmol inositol 1,4,5-trisphosphate and 50 pmol Ca2+. It is suggested that low molecular weight G proteins ADP-ribosylated by botulinum toxin C3 enzyme are involved in phospholipase C activation in Xenopus oocytes.

ADP Ribose Transferases↗
PubMed1994

Detection of west Nile and Japanese encephalitis viral genome sequences in cerebrospinal fluid from acute encephalitis cases in Karachi, Pakistan.

Reverse transcriptase-polymerase chain reaction (RT-PCR) on 24 cerebrospinal fluid (CSF) specimens collected between February and August 1992 detected genome sequence of West Nile (WN) virus in 8 specimens and Japanese encephalitis (JE) virus in a single specimen. The results, combined with the data by IgM-ELISA on CSF indicated that a significant proportion of acute encephalitis cases in Karachi, Pakistan, were caused by WN virus infection, while JE virus caused a small fraction.

Acute Disease↗
PubMed1994

New non-invasive rapid diagnosis of herpes simplex virus encephalitis by quantitative detection of intrathecal antigen with a chemiluminescence assay.

A technique for detecting herpes simplex virus (HSV) antigen in CSF by measuring the antigen-antibody complex-activated complement-stimulated chemiluminescence in normal granulocytes was applied to 17 CSF samples from 10 patients with herpes simplex virus encephalitis (HSVE), and 26 samples from 22 patients with a non-HSVE brain illness. All CSF samples taken from the 5th to the 38th day (including seven from the 5th to the 10th day) of HSVE were positive, whereas those for all non-HSVE samples were negative. This assay required only five hours to yield a result.

Adolescent↗
PubMed1994

Guillain-Barré syndrome following fulminant viral hepatitis A.

Guillain-Barré syndrome (GBS) developed soon after the onset of acute viral hepatitis A (HA) in a 62-year-old man. GBS associated with HA is extremely rare, even though HA is common. In a review of case reports the clinical features of GBS following HA could be summarized as follows: 1) Most of the patients are men. 2) GBS develops within 14 days after the onset of HA. 3) Facial nerve palsy is frequently present. 4) Proprioception is likely impaired in addition to superficial sensation. 5) The outcome of neuropathic symptoms is uniformly good, regardless of the degree of liver dysfunction as evaluated on the basis of alanine aminotransferase levels. These findings indicate that GBS following HA essentially does not differ from typical GBS.

Acute Disease↗
PubMed1994

The significance of herpes viral latency in the spiral ganglia.

To better understand the pathogenesis of idiopathic sudden hearing loss (ISHL), the possibility of latent virus infection in the spiral ganglion cell was considered. Only few spiral ganglion cells showed positive viral antigen after systemic guinea pig-specific cytomegalovirus (GPCMV) inoculation indicating the absence of hearing loss but the possibility of a subsequent latent infection. By using a modern molecular biological technique we have detected the herpes simplex virus type-1 (HSV-1) DNA in human spiral ganglia. The concept of establishing viral latency in the spiral ganglion cells with periods of reactivation fits with the clinical picture seen in ISHL, even though the mechanism of reactivation still remains unclear.

Adult↗
PubMed1994

The immune function and measles virus infection in three different socioeconomic child populations in Karachi, Pakistan.

The immune function as well as anti-measles virus antibody level were investigated with 111 children in Karachi who were classified into high-, middle- and low-income groups. No difference in the blood cell counts or the biochemical data among three groups indicates no marked difference in the general health conditions among them. In the low-income group, levels of IgG, IgA and anti-measles virus antibody were significantly higher than those in the other two groups. Although 30% of children of the low-income group kept extremely high levels of immunoglobulin, no significant correlation was observed between IgG levels and anti-measles virus antibody levels. In the high-income group, the level of IgM was significantly lower and the incidence of anti-measles virus antibody-negative children was high (7/38; 18.4%). These antibody-negative children kept lower immunoglobulin levels although they were over four years old. These results suggest that the living environmental conditions of these different socioeconomic groups vary greatly and hygienic conditions must influence the chance of encountering infectious pathogens including measles virus. The relation between living environment and risk of subacute sclerosing panencephalitis (SSPE) in child population of Krachi is discussed.

Antibodies, Viral↗
PubMed1994

Crow-Fukase syndrome: a case associated with vasospastic angina.

The patient is a 60-year-old man who developed numbness of the extremities, paralysis, hyperpigmentation of the skin, hypertrichosis, anasarca and chest pain at the age of 58 years. The diagnosis of Crow-Fukase syndrome was made and myeloma was not found. Prednisolone therapy was effective but chest pain reappeared every morning when prednisolone was tapered to 30 mg alternate day. Coronary arteriogram showed no stenosis but administration of acetylcholine into the coronary artery produced ST elevation in electrocardiogram, chest pain and coronary artery stenosis which were relieved by administration of nitrates into the coronary artery.

Acetylcholine↗
PubMed1993

Large and small coils in magnetic stimulation of the proximal portion of the facial nerve.

Magnetic stimulation (Magstim model 200) was performed with a large coil (14 cm in diameter) and a small coil (7 cm in diameter) in 12 healthy persons. Muscle potentials were obtained from ipsilateral orbicularis oris and nasalis muscles when magnetic stimulation was performed by placing a large or small magnetic coil at T6 or by placing a large magnetic coil at C4. The latency obtained by placing a magnetic coil at T6 was 1.2-1.3 ms (with a large coil) and 1.3-1.4 ms (with a small coil) longer, and the latency obtained by placing a large magnetic coil at C4 was 1.3-1.4 ms longer than the latencies obtained by stimulating at the stylomastoid foramen. The proximal portion of the facial nerve is considered to be stimulated transcranially when magnetic stimulation is performed by placing either a large or small coil at T6 or by placing a large coil at C4.

Adult↗
PubMed1993

Latent herpes simplex virus type 1 in human vestibular ganglia.

Viral infection has been considered to be a possible pathogenesis of vestibular neuronitis, and reactivation of the herpes simplex virus (HSV) is one of the most likely causes. However, it remains unknown whether the human vestibular ganglia contain latent HSV. We examined 26 vestibular ganglia from autopsied adults in search of HSV type 1 (HSV-1). To detect HSV-1, we used polymerase chain reaction (PCR), in situ hybridization and immunohistochemical staining. HSV DNA was detected in 6 of 10 vestibular ganglia using the PCR method. However, the latency-associated transcript (LAT) of HSV-1 was negative in all of the 16 vestibular ganglia examined. No HSV antigen was detected in any of the ganglia. These results indicate that HSV-1 is latently infected in the human vestibular ganglia, and that LAT is transcribed weakly or not at all.

Adult↗