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M Shimada

Publications and source records attributed to M Shimada.

At least 361 records · Page 20Linked to original sources
PubMed1997

[Neuronal migration disorders--pathogenesis and clinical manifestations: introductory remarks].

Cortical dysplasias caused by the destruction of neuron production and migration have been recognized as relatively common neuropathological findings among the children with intractable epilepsy and mental and/or physical handicaps. Together with various environmental factors, an increasing number of gene abnormalities have recently been identified as a cause of cortical dysplasias. However, the processes from the gene abnormality to the development of cortical dysgenesis remain unknown. In this symposium, the pathology, pathogenesis and MRI manifestation of neuronal migration disorders as well as intimate correlation with intractable epilepsy and neurosurgical treatment for this disorder, were reviewed by six experts.

Cerebral Cortex↗
PubMed1997

In vivo microradioautographic study of insulin binding in the skin of normal and NIDDM mice: with special reference to acanthosis nigricans.

Insulin bindings in the tissues and cells in the skin of non-diabetic (control) and genetically diabetic db/db (NIDDM) mice were investigated by in vivo microradioautography at 3 and 15 min. after intravenous injection of 125I-insulin. Specific insulin bindings were observed in the interfollicular epidermis, infundibulum, dermis, outer root sheath, sebaceous glands and blood vessels, but not in the hair shaft of the control mice. Although the specific bindings were seen in the interfollicular epidermis, infundibulum, outer root sheath and blood vessels in the NIDDM mice, the bindings were much less than those of the control mice at both 3 and 15 min. after 125I-insulin injection with an exception of the blood vessels at 3 min. The possible relationships between NIDDM and acanthosis nigricans from the viewpoint of insulin binding are considered.

Acanthosis Nigricans↗
PubMed1997

[Treatment of thoracic esophageal carcinoma which invades adjacent structure--significance of resection and combined therapy].

From January 1980 to December 1994, a total of 64 cases of thoracic esophageal carcinoma which invaded adjacent structure (A3) were resected and 35 cases were unresected in Kagoshima University Hospital. Adjacent structures were mainly trachea/bronchus, aorta or pulmonary vein. Combined resections were performed in 22 cases (34.4%), and no tumors remained in 12 cases (18.8%). One year survival rates and 50% survival time of the no residual tumor group were 25.7% and 8.5 months, while the rates of the residual tumor group were 15.7% and 5.1 months. But, there was no significant difference of survival rates according to the amount of residual tumor. On the other hand, 1-year survival rates and 50% survival time of unresected group were 3.1% and 4.5 months. As a postoperative adjuvant therapy, radiation was the most effective modality. As a result, operations should be done at first for the A3 carcinoma in which a complete combined resection is expected. On the other hand, radiation or chemotherapy should be selected for the cases in which the tumor may remain, even though combined resection is done.

Adult↗
PubMed1997

[Preventive use of diltiazem to suppress supraventricular tachyarrhythmia in the patients after esophagectomy].

We investigated the efficacy of preventive use of diltiazem to suppress supraventricular tachyarrhythmia such as paroxysmal atrial tachycardia (PAT) and atrial fibrillation (Af) in the patients who underwent transthoracic esophagectomy. We divided 52 patients into 2 groups; the diltiazem group (n = 26) and the control group (n = 26). In the diltiazem group continuous intravenous infusion of diltiazem (1-3mcg.kg-1.min-1) was started when the patient's heart rate remained over 110.min-1 without any predisposing factor. On the other hand, in the control group we did not use it preventively. In both groups, we did not restrict the use of antiarrhythmic agents if necessary. We recognized PAT or Af in the control group (54%) more often than in the diltiazem group (19%). PAT or Af seldom occurred after the 4th post-operative day in the both groups. Serum diltiazem concentrations of 9 patients after about 10 hours infusion showed great variation (between 30 and 250 ng.ml-1). In 7 of them the diltiazem concentration increased as the duration of infusion was prolonged. However, we did not observe bradyarrhythmia. We consider that the continuous diltiazem infusion is effective in suppressing supraventricular tachyarrhythmia after esophagectomy.

Aged↗
PubMed1997

Distribution of fiber types determined by in situ hybridization of myosin heavy chain mRNA and enzyme histochemistry in rat skeletal muscles.

We analyzed fiber types in rat skeletal muscles using a novel combination of in situ hybridization of myosin heavy chain (MyHC) mRNA, and enzyme histochemistry for succinate dehydrogenase (SD), which displayed metabolic properties. The fiber types were classified into the four major subtypes of I(beta/slow), IIA, IIX and IIB, and their intermediate types coexpressed two MyHC mRNAs: I and IIA, IIA and IIX, or IIX and IIB. The distribution of fiber types differed markedly in each skeletal muscle. The superficial region of limb muscles was composed mainly of fast-twitch fibers with oxidative-glycolytic and glycolytic activities, such as type IIX and type IIB. In contrast, the deep region was composed almost exclusively of type I and type IIA fibers both with oxidative activity. In this region, type IIA/IIX hybrid fibers were noted more frequently than type I/IIA and IIX/IIB hybrid fibers. In axial muscles, slow-twitch fibers and fast-twitch fibers composed predominantly of type IIB were distributed dispersively. The diaphragm and masseter showed a high proportion of type IIX and type IIB, respectively, to adapt to tissue-specific functional requirements and more frequently contained type IIX/IIB hybrid fibers than other observed muscles.

Animals↗
PubMed1997

[Trial of analysis of esophageal wall motion using optical flow method on esophagogram].

Several studies have indicated that the analysis of esophageal motion provides a valid means of identifying esophageal diseases. Although this motion can be seen on esophagogram, its quantification leaves much room for improvement. This study presents a computer method to quantify the apparent motion (optical flow) observed on sequences of esophagogram. This method computes at every point of a sequence of digitized images the two-dimensional velocity vector which characterized its motion from one image to the next image. The information on motion of the esophagus can be displayed by superimposing the local velocity vector on the original image.

Algorithms↗
PubMed1997

Forelimb muscle contraction induced by cerebral cortical stimulation after callosotomy: a myographic study in the mouse.

The effect of callosotomy upon motor control by the cerebral cortex on the forelimb was examined in the mouse. On the 10th day after callosotomy in the rostral or caudal part of the corpus callosum, the forelimb area of the cerebral motor cortex was stimulated intracortically with a microelectrode and muscle contraction of the forelimb was recorded by electromyography. Muscle contraction was observed in the contralateral forelimb in the mice of which callosal fibers were cut in the caudal part of the corpus callosum including the splenium corporis callosi as well as in the normal mice. On the other hand, muscle contraction was observed in the ipsilateral forelimb in the mice of which callosal fibers were incised in the rostral part of the corpus callosum including the genu, rostrum and trunk. The latency of the muscle contraction was about 0.5 msec in the both groups of the callosotomized mice, as well as in the normal mice.

Animals↗
PubMed1997

Distinct regulation of two hydroxysteroid sulfotransferases, ST2A1 and ST2A2, by growth hormone: a unique type of growth hormone regulation in rats.

In the present study, changes in the mRNAs of two major forms of hydroxysteroid sulfotransferases (STs), ST2A1 and ST2A2, have been determined in different growth hormone (GH) states. Hepatic ST2A1 mRNA was detected in both sexes of mature Sprague-Dawley rats. The level was 5 times higher in the females than in the males. ST2A1 mRNA was undetectable in GH-deficient animals, such as hypophysectomized rats and spontaneous dwarf rats. Continuous infusion of GH (mimicking the female secretory pattern) increased hepatic levels of ST2A1 mRNA in both GH-deficient animals. ST2A2 mRNA was detected only in the livers of mature female rats and in both sexes of GH-deficient animals. Intermittent injection of GH (mimicking male secretory pattern) strongly suppressed hepatic levels of ST2A2 mRNA in both GH-deficient animals. These results indicate that pituitary GH independently regulates both ST2A1 and ST2A2 at the pretranslational levels. These differences in GH responses between ST2A1 and ST2A2 are in good agreement with their female-dominant and female-specific modes of expression in normal rats. Furthermore, the present study demonstrates a unique response of ST2A2 to the secretory pattern of GH among the drug-metabolizing enzymes in rat livers, in which ST2A2 mRNA levels are suppressed by the male secretory pattern but not by the female secretory pattern of GH.

Animals↗
PubMed1997

Analysis of prognostic risk factors in hepatic resection for metastatic colorectal carcinoma with special reference to the surgical margin.

BACKGROUND: Liver resection for metastatic colorectal cancer has been established. Nevertheless, it is still controversial whether the surgical margin from the tumour edge to the cut surface of the liver is a significant prognostic factor in hepatic resection for colorectal metastatic liver cancer. METHODS: To clarify the prognostic risk factors in hepatic resection for colorectal metastasis, univariate and multivariate analyses were performed. Between April 1985 and April 1995, 31 patients underwent curative hepatic resection for metastatic colorectal cancer. The clinical and pathological factors were examined retrospectively. RESULTS: Overall 1-, 3- and 5-year survival rates of the patients were 92, 42 and 39 per cent respectively. Pathological study of 16 resected specimens with a solitary liver tumour revealed hepatic vein invasion by cancer cells in two of 16 cases, portal vein invasion in three, microsatellite lesions in two and biliary tract invasion in six cases. In resected specimens with a solitary tumour measuring less than 4 cm in diameter, one of these factors was observed in only two of nine cases, whereas in specimens with a solitary tumour measuring more than 4 cm in diameter, these factors were observed in six of seven patients (P < 0.05). The distance from the tumour edge to the intrahepatic invasion was less than 10 mm. With univariate analysis, tumour size of 4 cm or more in diameter, an interval of 6 months or less between colorectal and hepatic resection, four or more gross tumours, bilobar involvement and a resection margin from the tumour of less than 10 mm were found to be significant factors indicating a poor prognosis. Cox's proportional hazards model identified a tumour of 4 cm or more in diameter and a resection margin from the tumour of less than 10 mm as poor prognostic factors (P < 0.05). CONCLUSION: In treating metastatic colorectal cancer to the liver, the surgical margin should be more than 10 mm because occult intrahepatic invasion was always found to be located within 10 mm from the edge of the tumour.

Adult↗
PubMed1997

[Long-term follow up of idiopathic thrombocytopenic purpura in childhood].

Sixty children with idiopathic thrombocytopenic purpura (ITP) were followed up for 15 to 208 months (mean 120 months) from their first visit. Of these 65% (39 cases) were suffering from acute ITP and 47% of the patients were male. Of the 21 patients with chronic ITP 43% (9 cases) entered remission within five years from the onset of the disease. Conversely patients with chronic ITP for more than five years did not enter remission. Four patients with chronic disease were diagnosed to be other diseases (i.e. three cases were aplastic anemia, the other was Evans' syndrome) after one to four years from the onset. Four patients with chronic ITP for more than five years from the onset are now doing well without any severe bleeding problems. The patients who recovered have had neither problems nor complications. None of the patients died of a cerebral hemorrhage or severe bleeding. We consider that long term outcome of ITP in childhood would be better than that of adult cases.

Child↗
PubMed1997

[Dynamic MR hepatocholangiography with the SIP Fast GRE (saturation inversion projection fast gradient echo) method].

The purpose of this study was to assess the utility of dynamic MR hepatocholangiography with the Gd-EOB-DTPA enhanced SIP Fast GRE sequence in the hepatobiliary system. The SIP Fast GRE sequence was used for sequential imaging of the hepatobiliary system with a frame rate of 3 sec in a 256 x 192 matrix. Dynamic sequential acquisition was performed for 51 min before and after the injection of 30 mu mol/kg of Gd-EOB-DTPA in a rabbit. Dynamic images of the hepatobiliary system were obtained in the rabbit study. Dynamic MR hepatocholangiography provides better functional information than conventional MR cholangiography.

Animals↗
PubMed1997

[Use of BiPAP during weaning from mechanical ventilation in a patient with chronic obstructive pulmonary disease and acute respiratory failure].

In a 65-year-old man with chronic obstructive pulmonary disease and acute respiratory failure, bi-level positive airway pressure device (BiPAP) was used as part of weaning from mechanical ventilation. As an outpatient, he had had dyspnea of grade V (Hugh-Jones) and was hypercapnic (PaCO2 of 70 torr) and hypoxemic (PaO2 of 60 torr), while he was receiving oxygen at 2 L/min via nasal cannula. Acute respiratory failure developed due to pneumonia, and mechanical ventilation was begun. However, he could not be weaned with a standard weaning technique (T-piece). On the fifth day of mechanical ventilation, he was extubated and treatment with BiPAP was begun. He did not complain of dyspnea even though PaCO2 did not decrease, which indicates that BiPAP reduced the work of breathing. Use of BiPAP might make reintubation unnecessary when acute ventilatory failure develops soon after extubation in patients with COPD.

Acute Disease↗
PubMed1997

[Rational lymphadenectomy in patients with cervical nodes metastasis for carcinoma of the lower third esophagus].

Prognostic value of removing cervical nodes in patients with carcinoma of the lower third esophagus is extremely controversial. Of 93 patients with curative esophagectomy via trans-thoracic approach, cervical nodes were involved in five patients (13%), upper mediastinal nodes in 12 patients (30%), and para-aortic nodes in only one patients (3%) for 40 patients whose proximal part of the tumor invading the mid-esophagus from below. Of the remaining 53 patients with tumor extent confined to the lower third esophagus, cervical nodes were involved in only one patients (2%), upper mediastinal nodes in five patients (9%), and paraaortic nodes in six patients (11%). Three of the five patients with cervical metastasis whose proximal part of the tumor invading the mid-esophagus survived for at least 22 months or more following three-field lymphadenectomy. Removing the cervical nodes in patients with carcinoma of the lower third esophagus may have some role to improve the survival if the tumor invades the mid-esophagus from below.

Carcinoma, Squamous Cell↗
PubMed1997

Changes in the spine density on apical dendrites of pyramidal neurons in the motor area of the cerebral cortex after callosotomy: a study by a modified Golgi-Cox method in the mouse.

Changes in the number of spines on apical dendrites of pyramidal neurons in layers III and V of the motor area of the cerebral cortex were examined in the young adult mice (30-60 days old) by a modified Golgi-Cox method and laser scanning microscopy on the 1st, 6th, 10th and 12th days after callosotomy. The anterior part of the callosal body, including rostrum, genu and truncus corporis callosi, was sectioned with a razor blade. The numbers of spines on apical dendrites and their oblique branches of pyramidal neurons were counted at the level of layer II for layer III pyramidal neurons and at the level of layer III for layer V pyramidal neurons. The density of spines was increased on all these dendritic parts during 10 days after callosotomy; the diameters of spine stems and dendrites were also increased. These changes, however, appeared to be transient as they were decreased almost to normal level on the 12th day after callosotomy.

Animals↗
PubMed1996

Des-gamma-carboxy prothrombin and alpha-fetoprotein positive status as a new prognostic indicator after hepatic resection for hepatocellular carcinoma.

BACKGROUND: The aim of this study was to elucidate the usefulness of measuring the positive status of both des-gamma-carboxy prothrombin (DCP) and alpha-fetoprotein (AFP) preoperatively as a new prognostic indicator of hepatocellular carcinoma (HCC). METHODS: One hundred forty-seven patients who underwent curative hepatic resection for primary HCC were studied. The definitions of DCP and AFP positivity were: positive DCP > 0.1 AU/ml, and positive AFP > 50 ng/ml. The patients were classified into four groups according to their levels of positivity for DCP and/or AFP: Group 1 (n = 59), negative levels of both DCP and AFP; Group 2 (n = 28), negative DCP and positive AFP levels; Group 3 (n = 31), positive DCP and negative AFP levels; and Group 4 (n = 29), positive levels of both DCP and AFP. RESULTS: Patient survival and disease free survival in Group 4 were the worst among the four groups. By multivariate analysis, using Cox proportional hazards model, both the DCP- and AFP-positive status (in combination) and poorly differentiated histology were independent factors of poor prognosis for patient survival; and DCP- and AFP-positive status (in combination), poorly differentiated histology, positive intrahepatic metastasis, and tumor diameter over 5 cm were independent factors of poor prognosis for disease free survival. CONCLUSIONS: The combination of DCP- and AFP-positive status is a new prognostic indicator for patients with HCC after hepatic resection.

Adult↗