Search PubMed⌕ Search

Biomedical subjects

T Shimura

Publications and source records attributed to T Shimura.

At least 127 records · Page 7Linked to original sources
PubMed1989

[Beneficial effects of glucagon-insulin infusion on hepatic protein synthesis and DNA synthesis in partial hepatic ischemia].

To study the effects of glucagon-insulin (G-I) infusion on protein synthesis and DNA synthesis in a condition with partial hepatic ischemia, G-I or saline was infused via portal vein for 40 minutes before and after a period of partial hepatic ischemia or following a period of partial hepatic ischemia. Protein synthesis was measured by 14C-leucine incorporation into proteins in incubated liver slices and DNA synthesis by 3H-thymidine incorporation into DNA. Protein synthesis in the postischemic liver was significantly recovered faster and more completely in G-I treated rats. G-I infusion enhanced the DNA synthesis of postischemic liver significantly, peaking 48 hours after the period of partial hepatic ischemia. However, the dosage of G-I infused in this investigation couldn't increase the hepatic tissue blood flow measured by hydrogen gas clearance method. On the histological examination, mitotic index was significantly higher in G-I treated group than in control. These results suggest that G-I infusion could be beneficial effects on the liver in situation with partial ischemic injury and that G-I infusion could remarkably augment hepatic tissue repair following ischemic damage.

Animals↗
PubMed1989

[A clinical and pathological study of diffuse axonal injury].

There is increasing evidence from human and experimental studies that the most important factor governing the outcome in head injury is the severity of diffuse axonal injuries. The authors have experienced 18 cases of severe diffuse axonal injury which showed post-traumatic coma for more than 24 hours and CT findings resembling those of shearing injuries of the cerebral white matter such as have been presented by Zimmerman et al. (1978). The consciousness levels on admission were 6 or less on the Glasgow Coma Scale and all cases were shown clinically to have primary brain stem injury. The main type of head trauma resulted from road traffic accidents (83%). Skull fractures were found in only 5 cases (28%). These findings suggested that acceleration/deceleration injury produce in the patients severe diffuse axonal injury. Initial ICP was below 20 mmHg in 11 cases out of 13 (85%). Parenchymal small hemorrhagic lesions of initial CT were basal ganglia (7 cases), corpus callosum (4 cases), pons (4 cases), midbrain (3 cases) and thalamus (2 cases). Extraparenchymal hemorrhagic lesions included intraventricular hemorrhage (6 cases) and subarachnoid hemorrhage (6 cases). Two autopsied cases of severe diffuse axonal injury (acute case and chronic case) showed remarkable congestion and edema in the deep part of the frontal white matter. Microscopic examination revealed marked axonal degeneration including axonal retraction ball in the corpus callosum, in the internal capsule and in the white matter of the brain stem. Glasgow Outcome Scale of the 18 patients at 3 months after the trauma made us concerned that no patients indicated good recovery or even only moderate disability.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1988

Metabolic studies of the edematous cerebral cortex of the pyrithiamine-treated thiamine-deficient rat.

The pyrithiamine-treated rats produced by our method histopathologically exhibited the edematous lesion not only around the third ventricle and at the tegmentum of pons, as expected, but also in the cerebral cortex. These animals were, therefore, used in a biochemical study of the cerebral cortex, in particular, glucose metabolism. The results indicate an accumulation of lactate and severe impairment of the lipid metabolism in the edematous lesion of the cerebral cortex among the pyrithiamine-treated rats. The fact that oxygen consumption was hardly diminished, however, strongly suggested that amino acids were selectively supplied to the tricarboxylic acid cycle from the free amino acid pool.

Amino Acids↗
PubMed1988

[Gas shadow on CT scan following treatment in metastatic brain tumor--an autopsy case].

This is an autopsy case report of a 52-year-old woman with a brain abscess presenting as an intracerebral gas shadow on CT scan. She was admitted to our facility in June 1977, with disorientation and motor weakness of the right upper extremities. CT scan revealed two separate mass lesions in the frontal and occipital lobes on the left side. She was diagnosed as having metastatic carcinoma, and was treated by tumor removal, radiation therapy, and intraneoplastic local chemotherapy. Seventeen months later, she was readmitted with decreased mental activity, hemiconvulsion of the right side and high fever. CT scan revealed a peculiar round gas shadow on the left side of the temporal lobe. Ventricular drainage produced a cloudy cerebrospinal fluid with a protein concentration of more than 400 mg/dl and a leucocyte count of 138,200. An anaerobic culture of the ventricular cerebrospinal fluid revealed Escherichia coli. At that time, the lateral ventricle was irrigated several times with antibiotics. Unfortunately, however, she died one year after readmission. An autopsy was performed shortly after death, at which time serial coronal sectioning of the brain confirmed the CT scan findings presenting as an intracerebral gas shadow, and further demonstrated extension of the brain abscess from the left temporal lobe to the temporal horn of the lateral ventricle. The lesion in the left temporal lobe included yellowish pus with partially brownish capsules. A gas-containing brain abscess confirmed by CT scan and autopsy is rarely seen. The Hounsfield unit obtained from the abscess cavity by utilizing serial CT scan sometimes represents a condition requiring urgent treatment for brain abscess.

Adenocarcinoma↗
PubMed1988

[Histopathological study of a recurrent malignant glioma after an intratumor local injection of adriamycin].

This paper presents interesting morphological findings, which have never been previously reported, on tumor tissues after a local injection of an anticancer agent into three patients with malignant glioma. Following a craniotomy, 0.5 mg of Adriamycin (ADM) was injected through an Ommaya reservoir into the tumor bed. Light microscopy of the recurrent tumor and surrounding necrotic tissue revealed massive coagulation necrosis of the tumor tissues and fibrinoid necrosis of vascular channels, centering at the tip of the Ommaya tube. In the surrounding area of the massive coagulation necrosis, considerable reactive collagenous tissue, infiltrating lymphocytes and foreign body giant cell were found as well as so-called "organized" necrotic tissue. Electron microscopic findings of the same specimens revealed deposits of lipofuscin, lipid droplets, lysosome, abundant myelin figures and fibrous strands. It can therefore be assumed that this or similar anticancer agents, when may be directly incorporated into the residual tumor cells, are apparently reduced by coagulation necrosis and reactive collagenous tissue.

Adult↗
PubMed1988

[The effect of naproxen on fever following transcatheter arterial embolization of hepatic tumors].

In the cases of trans-catheter arterial embolization (TAE) for hepatic malignancies, naproxen has been evaluated for its antipyretic effect. Each patient not given naproxen manifested a remarkable and prolonged fever despite treatment by antibiotics. In those who received an administration of naproxen, however, a significant suppression of fever was achieved (P 0.01-0.001). No remarkable influence was found on the white blood cell counts, the serum GOT and LDH levels by the naproxen. Similarly, no untoward effect due to naproxen was found on the ulcerogenicity in the gastro-duodenum. Thus, for hepatic malignancies, naproxen could be useful in the symptomatic treatment of a fever following a TAE.

Adult↗
PubMed1988

[Clinicopathological studies of diffuse axonal injury--five autopsy cases].

In severe head injuries, delayed intracerebral hematoma appearing lately is noted due to the spread use of serial CT scan. The authors experienced the autopsy of 5 cases who presented diffuse axonal injury (DAI) among these new lesions in repeated CT scan findings and report the pathohistological findings. Subjects were as follows: The age range of the patients was 15 to 25 years. The consciousness levels of the 5 cases on admission were 6 or less by the Glasgow coma scale. CT findings of DAI were revealed hemorrhage of the corpus callosum, basal ganglia, tegmentum of pons, intraventricular, and acute brain swelling. Total clinical courses were 2 to 29 days, but most of them were 9 or less days. In the macroscopic findings, marked congestion and edema revealed mainly in deep part of the white matter of the frontal lobe in all 5 cases. Callosal disruption and hematoma adjacent the corpus callosum revealed in 4 out of 5 cases. Cerebral contusion with hemorrhage revealed in 3 out of 5 cases. Intraventricular hemorrhage and traumatic subarachnoid hemorrhage revealed in 2 out of 5 cases. Hemorrhage of basal ganglia and base of pons revealed in 2 cases. Microscopic examination of all 5 cases revealed pallor of myelin in the corpus callosum and white matter surrounding hemorrhagic lesion, and abnormal tortuous, swelling and fragmentation of axons in stained preparation. Axonal retraction ball was recognized in 3 out of 5 cases. In conclusion, five autopsied cases who presented acute brain swelling and hemorrhage of corpus callosum and tegmentum of pons in serial CT scan were examined.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1987

Incidental meningiomas in autopsy study.

Two hundred thirty-one cases of incidental meningiomas found at autopsy at the Montefiore Medical Center during the period from 1950 to 1982 were reviewed. The prevalence of incidental meningiomas increased with age, and was highest in people 80 years of age or older. The male to female ratio was 1 to 3. The relative size of the tumors also increased with age. Multiple meningiomas were found in 8.2% of the cases; none of them had stigmata of neurofibromatosis.

Adult↗
PubMed1987

[Effects of preoperative transcatheter arterial embolization (TAE) on the liver following partial hepatectomy in rats].

The safety of pre-operative transcatheter arterial embolization (TAE), especially on the relation to hepatic regeneration following partial hepatectomy, was evaluated in rats. TAE was done through a catheter cannulated into hepatic artery under laparotomy. The remarkable elevation of S-GOT and S-GPT levels were demonstrated a day after TAE, which returned to normal on third post operative day. No influence of the difference of embolized materials was seen on the changes of transaminase levels. TAE severely decreased hepatic microsomal functional mass measured by [14C]-aminopyrine breath test (ABT) and the recovery of microsomal functional mass was shown on the 14th day after TAE. Histologically, recanalization could not be revealed in embolized arterioles even on the 21st day after TAE. But trabecular pattern of hepatic lobules was preserved after TAE. The serious inhibition of DNA synthesis of regenerating liver was demonstrated when TAE was performed within 14 days prior to partial hepatectomy (p less than 0.001-0.05). The period from TAE to partial hepatectomy had a influence on the survival rate after partial hepatectomy, and when appropriate interval was taken after TAE, the survival rate increased significantly (33%-50% in 24 hours interval and 88% in 14 days interval). In conclusion, preoperative TAE remarkably suppressed hepatic regeneration after partial hepatectomy, and appropriate time when suppressed hepatic functional mass, such as microsomal functional mass measured by ABT, returned to pre TAE value was required to perform hepatectomy in safety.

Animals↗
PubMed1986

Multiple unit activities recorded from the medial preoptic area during copulatory behavior in freely moving male rats.

Multiple unit activities (MUAs) were recorded from the medial preoptic area (MPO) during copulatory behavior in freely moving male rats. The baseline firing rate in the male MPO was 19.6 spikes/s +/- 7.1 S.E. (n = 14), and it was increased by 36.7% when a female rat was introduced (26.8 spikes/s +/- 8.9 S.E., n = 14). The firing rate remained elevated until ejaculation. The maximum firing rate (53.5 spikes/s +/- 16.7 S.E., n = 14) was obtained specifically during pursuit-mounting behavior. This high frequency firing with pursuit-mounting behavior was, however, immediately inhibited for 8.2 s +/- 2.1 S.E. (n = 14) when mounting was followed by intromission. The firing-inhibition was further prolonged (120.9 s +/- 44.6 S.E., n = 14) when ejaculation was performed after mounting and intromission. In cases where mounting was elicited alone, a firing-inhibition was not observed and the firing rate after mounting returned to the average firing rate during copulatory behavior. These results suggest that the MPO neurons may play a major role in pursuit-mounting, intromission and ejaculation.

Action Potentials↗
PubMed1986

[Multifocal glioma of the brain--an autopsy case].

This is an autopsy case report of a 76 year old woman with multifocal glioblastoma multiforme. CT scan revealed three separate mass lesions in the left temporal lobe, left parietal lobe and right fronto-parietal lobes. CT-guided needle biopsy of the right fronto-parietal mass revealed glioblastoma multiforme. At autopsy, serial horizontal sections of the brain confirmed the CT scan findings and demonstrated extension of the tumor in the left parietal lobe to the subarachnoid space. The lesion in the right fronto-parietal region infiltrated a large area and was not demarcated. Microscopic examination of all three lesions revealed glioblastoma multiforme. The left temporal lobe tumor consisted of gemistocytic astrocytes predominantly. Reaction of the tumor to glial fibrillary acid protein (GFAP) antibody ranged from markedly positive in the gemistocytic astrocytes to negative in the anaplastic cells. The reported incidence of multifocal glioma is about 2-10%. The main pathophysiologic mechanisms invoked for this phenomenon are simultaneous neoplastic transformation and seeding from one tumor. The pathophysiology of this particular case is discussed in reference to the differences in the histopathology of the 3 separate foci of glioblastoma multiforme.

Aged↗