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T Kachi

Publications and source records attributed to T Kachi.

At least 55 records · Page 3Linked to original sources
PubMed1993

Subclinical phenotypic expressions in heterozygous females of X-linked recessive bulbospinal neuronopathy.

Four of 8 definite heterozygous female carriers determined by PCR amplification of tandem CAG repeat of the AR gene, from 4 families of X-linked recessive bulbospinal neuronopathy (X-BSNP) showed extensive high amplitude motor unit potentials in examined muscles although all subjects were neurologically normal. Plasma creatine kinase, myoglobin, myosin light chain, lactate and pyruvate were all normal even in the carriers who showed EMG abnormalities. Muscle biopsy showed a type 2 fiber preponderance and possible very mild type 2 fiber grouping in a carrier with an EMG abnormality. These results suggest that a mutant AR gene may express subclinical phenotypic manifestations in a subpopulation of the heterozygous females of X-BSNP.

Action Potentials↗
PubMed1993

[Immune system and hypophysis].

The immune system does not function in isolation from either nervous or endocrine system. Recent advances in biology have made it clear that there are many connections between immune system and hypothalamo-pituitary axis. Among them, relationship of cytokines to hypothalamus is of great interest. We reviewed functions of the cytokines such as interleukin, interferon and tumour necrosis factor. For example, IL-1 releases ACTH from the hypophysis being mediated by corticotropin releasing hormone in the hypothalamus. ACTH shows inhibitory effect on the immune system. Interferons, as well as interleukins bring fever and anorexia via opioid receptors in the hypothalamus. There are some evidences which show effect of IL-1 on the posterior hypophysis which secretes vasopressin and oxytocin. There are, however, many unknown mechanisms in this field. The resolution of the specific interactions between the immune system and the hypothalamo-pituitary axis is subject to further investigations.

Adrenocorticotropic Hormone↗
PubMed1992

Severity of X-linked recessive bulbospinal neuronopathy correlates with size of the tandem CAG repeat in androgen receptor gene.

The genetic mutation of X-linked recessive bulbospinal neuronopathy is amplification of a polymorphic tandem CAG repeat in the androgen receptor gene. We studied this CAG repeat in 26 Japanese patients from 21 families with X-linked recessive bulbospinal neuronopathy. The number of CAG repeats was significantly correlated with the age at onset of limb muscular weakness (r = -0.596, p < 0.001) and age-adjusted scored disability (r = 0.446, p < 0.03). The length of the CAG repeat therefore seems to be a determinant factor of clinical severity.

Adult↗
PubMed1992

Somatic motor efferents in multiple system atrophy with autonomic failure: a clinico-pathological study.

The myelinated fibers in the corticospinal tracts, ventral spinal roots, and the neurons in the ventral spinal horns were quantitatively examined in 8 autopsied cases of multiple system atrophy associated with autonomic failure. In these structures consisting of the somatic motor efferents, the main pathological feature was the size dependent-involvement of predominantly small-sized fibers and neurons. The small myelinated fibers were significantly depopulated, while the large myelinated fibers were well populated in the corticospinal tract. Neurons in the ventral horns were also involved, but those with a small diameter and located in the intermediate zone (Rexed's lamina VII, VIII) were markedly diminished. In the ventral spinal roots, in the fourth lumbar segments containing essentially no autonomic efferents, small myelinated fibers were also preferentially involved. These pathological changes in the small-sized fiber and neuron loss were examined in relation to the somatic and autonomic motor symptoms, particularly of pyramidal signs.

Aged↗
PubMed1992

Rough endoplasmic reticulum in the adrenaline and noradrenaline cells of the adrenal medulla: effects of intracranial surgery and pinealectomy.

UNLABELLED: Adrenal medullas in 53-day-old rats of the nonoperated (NO) group (n = 31), the sham-operated (SPX) group (n = 35) and the pinealectomized (PX) group (n = 38) were examined electron microscopically 14 days after surgery. Cell profiles showing solitarily and sparsely distributed rough endoplasmic reticulum (RER) were most frequent in the PX group (daily mean: 66.9%, 427/638), less in the NO (56.0%, 336/600), and least in the SPX (48.5%, 297/612) in adrenaline (A) cells (chi 2-test: P less than 0.001), while most frequent in the NO group (68.8%, 340/494), less in the PX (64.3%, 303/471), and least in the SPX (57.4%, 256/446) (P less than 0.005) in noradrenaline (N) cells. Individual variation was less in A cells than in N cells. Cell profiles showing a large accumulation of RER was more frequent in A cells (NO:8.5%, SPX:13.1%, PX:7.7%) than in N cells (NO:2.8%, SPX:4.5%, PX:4.7%) (controls: P less than 0.001). Sham pinealectomy increased a large accumulation of RER in A cells (P less than 0.02) and a small aggregation of RER in N cells (P less than 0.005) with opposite effects of pinealectomy (P less than 0.005, P less than 0.025). Pinealectomy decreased a small aggregation of RER without effects of sham pinealectomy in A cells (P less than 0.001). CONCLUSIONS: (1) Accumulation or aggregation of RER in adrenomedullary chromaffin cells was influenced from the pineal gland either as or without effects of intracranial surgery, and (2) RER in adrenomedullary chromaffin cells showed differences due to cell types.

Adrenal Medulla↗
PubMed1992

Central motor and sensory conduction in X-linked recessive bulbospinal neuronopathy.

Central conduction was studied in 12 patients with X-linked recessive bulbospinal neuronopathy (XBSN) using percutaneous electrical cortical, cervical and lumbar stimulation and somatosensory evoked potentials (SEPs). The central motor conduction time from the motor cortex to the cervical and lumbar segments of the spinal cord was normal in XBSN. SEPs, however, were abnormal or central sensory conduction time was prolonged in patients with XBSN. These results are consistent with the clinicopathological findings of XBSN in which the primary sensory neurons are involved as well as the lower motor neurons in the CNS, whereas the upper motor neurons are well preserved.

Adult↗
PubMed1991

[Central motor conduction time in the pseudopolyneuritic form of amyotrophic lateral sclerosis].

Central motor conduction time (CMCT) from the cerebral motor cortex to the cervical segment of the spinal cord (C-CMCT) and CMCT from the cortex to the lumbar segment of the spinal cord (L-CMCT) were estimated using percutaneous electrical cortical, cervical and lumbar stimulation in 8 patients with pseudopolyneuritic form of amyotrophic lateral sclerosis (ALS). The results were compared to those in 18 patients with bulbar and common forms of ALS and 13 normal control subjects. Both the C-CMCT and the L-CMCT were remarkably prolonged in pseudopolyneuritic form of ALS as well as in bulbar and common forms of ALS. These results were consistent with the morphological findings that the large myelinated fibres in the corticospinal tract are depleted in pseudopolyneuritic form of ALS in which deep tendon reflexes are hypoactive and pyramidal sings are not obvious. The evaluation of CMCT is suggested to be useful for diagnosis of ALS in which upper motor neurone disorder is not manifested.

Adult↗
PubMed1990

Effects of pinealectomy on the mitotic activity of adrenomedullary chromaffin cells in relation to time of day.

The frequency of mitoses of adrenaline (A) cells and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male, 53-day-old Holtzman rats (n = 133) was investigated by means of light microscopy. Animals were killed at eight time points during a standardized 24-h light-dark (12:12) cycle 14 days after surgery. Mitotic indices (n/1,000) were determined in sections of adrenal medulla fixed with glutaraldehyde and OsO4. Overall frequency of mitoses was extremely low (mitotic index: 0.73 = 115/157,223). Daily mean mitotic index was maximum in A cells (0.83) and minimum in N cells (0.52) of PX group but did not show statistically significant differences between cell types or experimental groups. Neither cell type in NO animals showed 24-h changes in mitotic index, but cells in SPX animals did, with highest value in the late dark phase and lowest in the late light phase, when values of two cell types were combined (P less than 0.01-0.001). In PX animals, mitotic index followed a similar but more distinct 24-h change in A cells (P less than 0.009), but not in N cells, resulting in different time-of-day changes between two types of cells (P less than 0.01-0.05). The mitotic index was higher in PX than in control (NO and SPX) animals in the middark phase (P less than 0.05) and lower in operated (SPX and PX) than in nonoperated (NO) animals from late light to the early dark phase, suggesting that the latter was possibly due to a residual effect of the surgery. These results are consistent with the interpretation that the pineal has an inhibitory action on A cells and may coordinate the two types of cells in their mitotic activity, especially in the middark phase of the daily cycle.

Adrenal Medulla↗
PubMed1990

[Ageing and central motor conduction time].

The corticomotoneuronal pathway in the aged was studied using the technique of percutaneous electrical stimulation of the brain and the spinal cord. Central motor conduction time (CMCT) from the cerebral motor cortex to the cervical segment of the spinal cord (C-CMCT) was measured in 26 intact volunteers (20-85 years old) by substracting the latency to onset of EMG activity of the thenar muscle after cervical stimulation from the latency to onset of EMG activity of the same muscle after cortical stimulation. The latencies to onset of action potential of the anterior tibial muscle after cortical stimulation and the onset of action potential of the same muscle after lumbar stimulation were also measured in 11 volunteers (aged 46-67 years), and the difference between the two latencies was evaluated as the central motor conduction time from the cortex to the lumbar segment of the spinal cord (L-CMCT). Mean C-CMCT was 5.1 ms. and mean L-CMCT was 12.8 ms. Neither was related to the patient's height or age. There was no difference in either C-CMCT or L-CMCT between males and females. The results suggested that the conduction of the pyramidal tract is not affected by age, and this must be recognised when motor functions in the aged are studied.

Adult↗
PubMed1990

[Spatial distribution of the peripheral nerve lesion in polyarteritis nodosa].

We have examined the peripheral nerves in four patients with polyarteritis nodosa. They were consisted of two males and two females with the age of 70, 49, 65 and 75 years respectively. The sciatic and posterior-tibial nerves, sural nerves, ventral and dorsal spinal nerve roots, dorsal ganglia and spinal cord were removed at autopsy. Particularly, the sciatic and posterior-tibial nerves were removed as a whole and suspended in a glass cylinder with a weight and fixed in 1.5% glutaraldehyde and 0.05 M phosphate buffer, pH 7.4 for 16 hours. The nerve fragments of every 3 to 3.5 cm along the sciatic and posterior-tibial nerve were examined on conventional paraffin-embedded and epon-embedded sections, and osmicated teased-fibers. Necrotizing angitis was commonly present in the epineurium of the sciatic and posterior-tibial nerves in all four patients. Although necrotizing angitis was diffusely distributed in the proximal to distal portions of the nerve, loss of myelinated fibers, occurred only in the distal to mid-lower portions of the sciatic nerve. There was no substantial myelinated fiber loss in the proximal part of the sciatic nerve in three of four cases. Myelinated fiber loss in the fascicle was central fascicular or multiple-focal in pattern in the proximal portions of the nerve, but was diffuse in more distal portion of the posterior tibial nerve. Segmental demyelination and myelin irregularity in the teased-fiber preparation were more prominently observed in the proximal portions, but fibers with axonal degeneration were more frequent in the distal portions of the nerve.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

[Pathology of the peripheral nervous system in polyarteritis nodosa: a clinico-pathological study of two autopsy cases].

Peripheral nerves from the two autopsied cases with polyarteritis nodosa were pathologically examined. Case 1 was a seventy-year-old female, complaining of numbness and weakness of the extremities. Sensory deficits in all modality with induced dysesthesia were distributed as a mode of overlapping mononeuritis multiplex in the distal portion of extremities. Motor involvement was also noted in extremities in disarray-accentuated pattern. Extensive steroid hormone therapy was performed and remarkable improvement in clinical sign was temporarily obtained. Relapse with bowel involvement was a cause of the death. In the post-mortem examination, central fascicular degeneration with the loss of large myelinated fibers were seen at the middle portion of upper limbs in median nerve and at the lower mid-thigh in sciatic nerve. In the distal portion of those nerves, diffuse extensive loss of large myelinated fibers in the fasciculus were observed. Some of small thin myelinated fibers in the central fasciculus or distal portion of nerves were thought to be regenerated in nature. Accumulation of cell organelles in the axonal swellings were frequently occurred in the proximal to the ischemic site. Case 2 was a seventy five-year-old female with a both motor and sensory involvement in the distal extremities. Right pulmonary effusion and extensive subcutaneous hemorrhage and necrotic gangrene in the leg was also noted. Post-mortem examination of peripheral nerves revealed a presence of central fascicular degeneration in the distal sciatic nerves and nearly complete loss of myelinated fibers in the distal nerves. Ventral and dorsal roots and dorsal root ganglia were well preserved.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

Quantitative cytological analysis of functional changes in adrenomedullary chromaffin cells in normal, sham-operated, and pinealectomized rats in relation to time-of-day: II. Nuclear-cytoplasmic ratio, nuclear size, and pars granulosa of nucleolus.

Adrenaline(A)- and noradrenaline(N)-cells in the adrenal medulla of nonoperated (NO), sham-operated (SO), and pinealectomized (PX) male rats (n = 125) were investigated by quantitative electron and light microscopy. Animals were killed at eight time points during a standardized 24-h, light-dark (12:12) cycle 14 days after surgery. Nuclear-cytoplasmic (N/P) ratios, diameters of nuclei, and the frequency of nucleoli showing a large amount of pars granulosa (granulated nucleoli), were the primary characteristics studied. Major findings include the following: 1) The frequency of low N/P ratios over a 24-h period tended to be higher in PX animals than in controls in A-cells, as shown in large cell profiles (P less than 0.02); but such a tendency was not apparent in N-cells. Daily mean nuclear diameters were similar among the three experimental groups. 2) The 24-h changing pattern of phase relations in the frequency of low N/P ratio and nuclear size differed between A- and N-cells in NO and SO but not in PX animals. 3) The frequency of granulated nucleoli in A-cells was much higher in PX animals than in NO and SO animals throughout a 24-h period (P less than 0.018), especially from the late light to early dark phase (P less than 0.003), and higher in A-cells than in N-cells generally (P less than 0.0009). Pinealectomy thus caused increases in the cytoplasm and in the pars granulosa of the nucleolus in many A-cells; changes in N-cells were less apparent. This suggest a disturbed balance and coordination between A- and N-cell systems of adrenal medulla following pinealectomy.

Adrenal Medulla↗
PubMed1988

Quantitative cytological analysis of functional changes in adrenomedullary chromaffin cells in normal, sham-operated, and pinealectomized rats in relation to time of day: III. Nuclear density.

The sizes of adrenaline (A) and noradrenaline (N) cells in the adrenal medulla of nonoperated (NO), sham-operated (SPX), and pinealectomized (PX) male rats (n = 126) were investigated by quantitative light microscopy. Animals were killed at eight time points during a standardized 24-h, light-dark (12:12) cycle 14 days after surgery. Nuclear densities were measured in semithin sections of epon-embedded specimens, initially fixed with glutaraldehyde and OsO4. Major findings are as follows. 1) The mean size of adrenomedullary A cells throughout 24 h (P less than 0.001), especially in the dark phase (P less than 0.001) but not in the light phase, was larger in PX animals than in NO and SPX animals. There were no statistically significant differences in the size of N cells among the three experimental groups in either the dark phase or the light phase. 2) The sizes of A and N cells showed time-of-day changes in the NO and the SPX animals but not in the PX animals. The temporal relationship of 24-h changes in the cell size tended to be different between A and N cells in the NO and the SPX animals but not in the PX animals. 3) The cell size was apparently larger in A cells than in N cells in each experimental group. Pinealectomy thus caused hypertrophy of A cells, especially in the dark phase, but not apparently hypertrophy of N cells. Concerning the pinealectomy effects in relation to the time of day, the results support the hypothesis of pineal action being phase-tuning and coordinating of at least some circadian systems.

Adrenal Medulla↗
PubMed1988

Effect of L-threo-3,4-dihydroxyphenylserine on muscle sympathetic nerve activities in Shy-Drager syndrome.

We observed changes in postganglionic efferent discharges of muscle sympathetic nerve (muscle sympathetic activity, MSA) microneurographically before and after the oral administration of L-threo-3,4-dihydroxyphenylserine (L-threo-DOPS), a precursor of norepinephrine, in a patient with Shy-Drager syndrome and irregular fluctuations of blood pressure. Before drug administration, MSA was only rarely observed with the patient in the supine position. There was a slight increase in MSA during head-up tilting to 40 degrees, and orthostatic hypotension (OH) occurred just after the body was tilted head upward to 40 degrees. MSA became prominent 30 minutes after the oral administration of 200 mg of L-threo-DOPS while the patient was in a 40 degree head-up position, and the OH was improved. The MSA discharge rate decreased and OH reappeared 3 hours after oral administration, when the plasma concentration of norepinephrine was at its highest level. We suggest that the OH improved mainly because of the increase in MSA due to L-threo-DOPS, and that the drug may activate sympathetic outflow at a site proximal to the sympathetic ganglion.

Autonomic Nervous System Diseases↗
PubMed1987

Motor cortex stimulation in intact man. 1. General characteristics of EMG responses in different muscles.

This paper is the first of two papers describing our five-year experience with the technique of electrical stimulation of the human motor cortex. In this first paper we illustrate the basic distribution and behaviour of electromyographic responses in limb muscles to anodal stimulation of the motor cortex in intact, awake human subjects. These responses may be recorded at short latency, with estimates of conduction velocities from the brain to the spinal cord suggesting transmission in rapidly conducting pathways, such as the corticomotoneuronal component of the corticospinal tract. The site at which the stimulus activates these motor pathways to produce responses at such short latency is likely to be at, or adjacent to the origin of these major descending motor pathways in the cerebral cortex. The best stimulating sites for activation of arm or leg muscles corresponds to the known somatotopic arrangement of the cerebral cortex. The electromyographic response characteristics are different in the contracting, as compared with the relaxed muscle; the EMG response latency shortens, its size becomes larger and its threshold is lowered when the muscle is voluntarily made to contract. The mechanisms that are responsible for these characteristics are examined in the following paper.

Adult↗