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Biomedical subjects

T Shimura

Publications and source records attributed to T Shimura.

At least 91 records · Page 5Linked to original sources
PubMed1994

Quantification of serum-soluble HLA class I antigens in patients with gastric cancer.

The amount of sHLA-I in serum was examined in 74 patients with gastric cancer and 15 normal healthy controls. For mAbs, W6/32 specific for HLA-A, -B, -C, and biotin IOT2 specific for HLA class I associated with beta 2 microglobulin, were used to determine the values of sHLA-I using an ELISA. The patients in stage-IV gastric cancer showed lower values of sHLA-I (445.4 +/- 247.1 ng/ml) than those in stage I (725.9 +/- 575.8 ng/ml), stage II (752.8 +/- 255.0 ng/ml), and normal controls (868.9 +/- 715.0 ng/ml) (P < 0.05). In analysis of the patients with HLA-A24, the allele that has been reported to secrete more sHLA-I than other alleles, the results were nearly the same. These results suggest that the secretion of sHLA-I is low in patients with very advanced cancer. However, there was no correlation between the sHLA-I level and the metastasis or prognosis in longitudinal studies in 11 patients.

Adult↗
PubMed1994

Some critical factors involved in formation of conditioned taste aversion to sodium chloride in rats.

Some factors concerning acquisition and retention of conditioned taste aversions (CTAs) were behaviorally examined in the rat. In the CTA paradigm, aqueous solution of 0.1 M NaCl was used as the conditioned stimulus (CS) and an intraperitoneal (i.p.) injection of 0.15 M LiCl was employed as the unconditioned stimulus (US). In experiment 1, CTAs to 0.1 M NaCl were examined in both forward (CS-US) and backward (US-CS) conditioning paradigms. Reliable CTAs were produced in the US-CS conditioning paradigm when the US-CS interval was less than 10 min, as well as in the CS-US conditioning paradigm. In experiment 2, strong CTAs to 0.1 M NaCl were established when water-deprived rats made at least 500 continuous licks, corresponding to 2.5 ml intake and 2 min of drinking time. In experiment 3, effects of gustatory deafferentation on CTA formation were studied. Only the chorda tympani played an important role in acquisition and retention of CTAs to NaCl solutions. These results indicate that strong CTAs can be acquired to 0.1 M NaCl, if its taste information which is conveyed via the chorda tympani during the 500 continuous licks is followed by LiCl-induced sickness.

Animals↗
PubMed1994

Melanotic neuroectodermal tumor of infancy in the skull associated with high serum levels of catecholamine. Case report.

The case of a 5-month-old boy with a left retromastoid melanotic neuroectodermal tumor of infancy is presented. The tumor extended from the subcutaneous tissue of the occiput to the cerebellar hemisphere. Histologically, the epidural part of the tumor was composed of undifferentiated neuroblasts, dense connective tissue, and glandular structures lined by melanin-containing cuboidal cells, whereas the subdural part contained differentiated neuroblasts and melanin-containing cells. The preoperative high serum levels of adrenaline, noradrenaline, vanillylmandelic acid, and neuron-specific enolase returned to normal after two operations and two cycles of chemotherapy; however, the dopamine level was mildly elevated. These data and immunohistochemical and ultrastructural findings strongly suggest that melanotic neuroectodermal tumor of infancy is derived from the neural crest.

Catecholamines↗
PubMed1994

[Electron microscopic and immunohistochemical studies of acute stages of severe brain injury in rats].

Few morphological studies on fluid-percussion experimental models using mechanically produced severe brain injury have been reported. This study was initiated to evaluate light and electron microscopic and immunohistochemical findings in severe brain injury models using rats. The experimental rats and the methods used were as described for a fluid-percussion model. Fluid-percussion models of traumatic brain injury produce injury rapidly by injecting fluid volumes into the epidural space of the temporal lobe. We used 5 rats which sustained various degrees of injury by high (7.0 atm), medium (5.6 atm) and low (3.5 atm) magnitudes of impact and sham control. The rats were sacrificed and perfused transcardially with buffer solution followed by 2.5% glutaraldehyde at intervals of 24 hours, 3 days, and 7 days, and there were normal and sham control groups. In this immunohistochemical study, monoclonal antibody to 70 kilodalton neurofilament subunit has been used in a standard Avidin-Biotin Complex Kit (DAKO). Microscopic findings of the animals revealed subarachnoid hemorrhage, lateral IIIrd ventricular hemorrhage, and rarefaction and petechial hemorrhage of the local contusional lesion. In the medium level injury, there was a marked petechial hemorrhage in the corpus callosum and subependymal area. In the high level injury, there was marked edema in the white matter of the ipsi and contralateral cerebral hemisphere, and multiple petechial hemorrhage in the brain stem and cerebellum. Microscopic findings in the corpus callosum, subependyma and brain stem in the vicinity of petechial hemorrhage revealed a large number of axonal swellings, but in these specimens only a few typical axonal retraction balls were seen using Bodian and immunohistochemical stains.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

[Neuropathological study of battered child syndrome: eight autopsy cases].

The term "battered-child syndrome" was coined by Kempe in 1962. The morphology of brain lesions in abused children is rarely reported in Japan. This clinicopathological entity in the central nervous system is characterized by retinal hemorrhages, subdural and subarachnoid hemorrhage. However, reports on microscopic findings of intracerebral lesion are fewer than those on macroscopic findings of scalp, skull and intracranial cavity. This study was performed on 8 cases of battered children who were autopsied. They consisted of six female and two male infants. The age ranged from one week to four years old. The causes of the injuries were shaking in four cases, throwing in three cases, dropping in two cases and strangling in one case, mostly in combination. CT scans were examined for three cases. CT scan revealed acute cerebral swelling and acute subdural hematoma with interhemispheric blood clot in three cases and multiple low density area in one case. Evacuation of the subdural hematoma and external decompression was performed in one case. The survival period from injury to death was one day in four cases, and 2, 3, 9 and 41 days in the others. In the gross anatomical findings there are many excoriations and bruises of the face and scalp in five cases, widespread subcutaneous hematoma in all cases and skull fracture in only two cases. The brain weight was exceedingly heavier than normal brain weight by age in five cases. In the macroscopic findings, there were marked cerebral swelling and cerebral herniation in all cases, traumatic subarachnoid hemorrhage in six cases, and thin widespread acute subdural hematoma with interhemispheric clot in four cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Axons↗
PubMed1994

[Correlation of serial MRI and histological findings following intra-tumor local chemotherapy for malignant brain tumor].

Serial magnetic resonance imaging (MRI) studies on patients with malignant brain tumor after postoperative adjuvant therapy have been rarely reported. Leukoencephalopathy after such treatment is a well-known serious adverse effect, which we studied by serial MRI after postoperative adjuvant therapy in 15 patients with malignant brain tumors (anaplastic glioma 6, astrocytoma Grade III 5, astrocytoma Grade II 2, and metastatic brain tumor 2) (Table 1). All patients were examined by MRI, more than twice postoperatively. Adjuvant therapy was as follows: adriamycin (ADM) (0.5 mg) was injected through Ommaya reservoir into the tumor bed at the craniotomy. The usual total dose of ADM was 5.0 mg. In three of 15 patients, local methotrexate chemotherapy was added. Fourteen patients received a course of local irradiation 58 Gy on average combined with local ADM chemotherapy. Histological findings of three autopsy cases and ten reoperated ones were correlated with the serial MRI. Consecutive MRI were examined one and three months after adjuvant therapy. The results were as follows: One month after adjuvant therapy, thin and high signal intensity areas could be seen in the marginal zone of the tumor cavity on the gadolinium-enhanced T1-weighted MRI. High signal intensity areas could also be seen in the operative cavity on the T1-weighted MRI, which were suspected to be residual hematomas. In one patient, a high, diffuse and widespread signal area could be seen on T2-weighted MRI, suggesting leukoencephalopathy. Three months after adjuvant therapy, a high thick signal intensity area could be seen in the marginal zone of the tumor cavity and along the route of the Ommaya tube on the gadolinium-enhanced T1-weighted MRI, but there was no mass effect in these space taking lesions. In five cases, a low signal intensity area could be seen in the porencephalic cystic lesion, in one of which septum formation of cystic cavity was detected on the gadolinium-enhanced T1-weighted MRI. Morphologically, there was massive coagulation necrosis in the tumor cavity, but in the vicinity of the cystic wall abundant fibrous connective tissue was found to correspond with the high and thick signal intensity area on the above-mentioned gadolinium-enhanced T1-weighted MRI.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1993

c-Fos expression in the parabrachial nucleus after ingestion of sodium chloride in the rat.

The distribution of evoked expression of the proto-oncogene c-Fos was immunohistochemically examined in the parabrachial nucleus (PBN) of the rat after free ingestion of NaCl and some other taste solutions. C-Fos-like immunoreactive neurones (c-Fos neurones) were densely observed in the external lateral subnucleus (els), central lateral subnucleus (cls), and the central part of the medial subnucleus (ms). The finding that the number of c-Fos neurones decreased dramatically in the ms after treatment of the tongue with amiloride or after dissection of the chorda tympani suggests that the taste information of NaCl projects mainly to the ms. The functional significance of the els and cls is discussed, and it is suggested that the els is a recipient zone for general visceral inputs and the cls is concerned with palatability of the liquids ingested. The present study has proved that c-Fos immunoreactivity is a useful anatomical marker for activated neurones in the PBN during ingestive behaviour.

Amiloride↗