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Biomedical subjects

M Matsumae

Publications and source records attributed to M Matsumae.

At least 37 records · Page 2Linked to original sources
PubMed1995

Neuronal overmaturation in dysraphism: ontogenic expression of neuropeptides in the fetal brain and developmental anomalies in exencephaly.

Starting from knowledge obtained in our previous studies of experimental dysraphism in chick embryos, the entity of neuronal overgrowth observed in exencephaly was further investigated. The ontogenic expression of neuron-specific enolase (NSE), vasoactive intestinal polypeptide (VIP), and somatostatin was analyzed both in chick exencephaly of the natural product and in normal chick fetuses by carrying out immunohistochemical studies. In normal fetuses, immunostained elements positive for NSE first appeared in the spinal gray matter on postincubation day 16 and increased in intensity during the fetal period. By postnatal day 2, the cerebral peduncle, brain stem neurofibers, molecular layer of the cerebellum, corpus striatum, and piriform cortex became immunoreactive. No immunohistochemical reaction to VIP was observed during these stages. Somatostatin-positive elements were not identified during the fetal period, except in limited regions, such as the corpus striatum, which appeared to have weakly positive staining on day 21. The exencephalic fetuses, however, demonstrated extremely advanced neuronal maturation, with intense immunoreactivity already being manifest in various regions, including the corpus striatum, piriform cortex, spinal gray matter, and brain stem nuclei, on day 16 of the fetal period. Somatostatin-positive elements also appeared at this stage in chick exencephaly, but such immunoreactivity was localized, particularly in the overgrown foci. The present study showed that the neuronal maturation process in some neurons of exencephalic brain and spinal cord was definitely further advanced than that in normal controls. A possible clinical application of NSE and somatostatin measurement as markers for dysraphic states in the fetus is suggested.

Amniotic Fluid↗
PubMed1993

The neurobiology of normal pressure hydrocephalus.

Normal pressure hydrocephalus (NPH) is an intriguing problem in cerebrospinal fluid (CSF) and brain parenchymal physiology. This article presents what is known about its pathophysiology as well as its clinical presentation and treatment.

Humans↗
PubMed1991

Laser-assisted fibrinogen bonding of vascular tissue.

Characterization of the stress-strain profiles of welded tissue would provide an additional means of analyzing this new technology and comparing it with alternative anastomosing techniques. Rabbit longitudinal aortotomies were repaired with either 7-O polypropylene sutures or an 808-nm diode laser (power density, 4.8 watts/cm2) after topical application of fibrinogen mixed with indocyanine green dye (peak absorption, 805 nm). The rabbits were sacrificed between 0 and 28 days, and the fresh aortic specimens were strained axially in diluted plasma solution until ultimate breakage occurred in order to produce a stress-strain profile graph. No significant differences were noted between sutured and bonded aorta at any time interval. Nonincised aortic tissue (378 lb/in2) withstood significantly higher stress (P less than 0.05) than both sutured (257 lb/in2) and bonded (210 lb/in2) groups at the time of creation. By 7 days after operation, however, no significant differences were noted among any of the three groups. At 28 days after operation, the laser-bonded aorta was significantly stronger than the control aorta (P less than 0.05). The only significant difference in modulus (stretchability) identified the sutured aorta (373 lb/in2) to be more rigid than the control aorta (231 lb/in2) (P less than 0.05). Both sutured and laser-bonded anastomoses are weaker than control aorta initially; however, after an early critical period, both treatments achieve the strength of control aorta. By 1 month postoperatively, sutured anastomoses have the disadvantage of being less distensible.

Animals↗
PubMed1990

Energy metabolism in kaolin-induced hydrocephalic rat brain. Assessed by phosphorus (31P) magnetic resonance spectroscopy and the diversity of lactate-dehydrogenase and its isoenzyme patterns.

Energy metabolism in kaolin-induced hydrocephalic rat brain was assessed by means of 31-phosphorus magnetic resonance spectroscopy and measurement of the activity of lactate dehydrogenase (LDH) as well as its isoenzyme patterns. Decreases in beta-adenosine triphosphate and phosphocreatine were observed in hydrocephalic rat brains. While the intracellular pH was decreased at 2 to 4 weeks, it showed some recovery 6 weeks after injection of kaolin. The activity of LDH increased in the hydrocephalic state, and its isoenzyme-pattern changes were as follows: the LDH5 fraction was predominant in 1-week to 4-week rats while the LDH4 fraction was predominant in 4-week rat brains, and at 6-weeks, the LDH4 and LDH5 fractions were decreased. These data from rat brains with kaolin-induced hydrocephalus indicate that anaerobic glycolysis is the primary pathway of energy metabolism in the acute hydrocephalic state, while in the chronic state the emphasis shifts to aerobic glycolysis.

Animals↗
PubMed1990

A flexible sutureless intraluminal graft that becomes rigid after placement in the aorta.

A new sutureless intraluminal graft has been developed with a ring made of a coiled, overlapping, stainless steel spring with ratchets in one overlapping end. This graft is flexible during insertion but becomes rigid after proper intraaortic placement as the spool is dilated and the ratchest lock into position. The new graft was implanted in 10 dogs and was evaluated histologically and angiographically at various intervals. No ring dislodgment, aortic rupture, stenosis, or aneurysmal dilation was observed. The flexible component of this graft allows it to be introduced and secured in place easily and provides a technical advantage compared with the clinically used rigid intraluminal graft.

Animals↗
PubMed1990

[A case report: persistent primitive hypoglossal artery aneurysm].

The authors describe a case of persistent primitive hypoglossal artery aneurysm in a 42-year-old woman who had complained of headache, mainly in the occiput, for 5 days prior to admission. Because of a sudden exacerbation of the headache associated with vomiting, she was hospitalized on July 31, 1988. On admission, a cranial computed tomography scan demonstrated a high density lesion in the basal cisterns which suggested subarachnoid hemorrhage (SAH). Right carotid angiography revealed a persistent primitive hypoglossal artery and an aneurysm arising from this artery at the junction of the posterior inferior cerebellar artery. Bilateral vertebral arteries were shown to be hypoplastic. This was followed by a right suboccipital craniectomy on the 6th hospital day at which time a neck clipping was made. Her postoperative course was uneventful. On discharge on August 22, she was ambulatory and had no neurological deficit except for a mild hoarseness which developed after surgery. Well over one hundred cases of persistent primitive hypoglossal artery aneurysm have been reported. However, as far as we could discern, there have been only 9 cases of persistent primitive hypoglossal artery aneurysm including this present case. Most of the cases had SAH due to the rupture of these aneurysms with favorable outcome after the surgery. In addition, some embryological considerations were made.

Adult↗
PubMed1989

Quantification of cerebrospinal fluid shunt flow rates. Assessment of the programmable pressure valve.

Shunt placement diverting cerebrospinal fluid (CSF) has been the treatment of choice for hydrocephalus for the past several decades. However, the procedure often requires revisions owing to excessive drainage, low CSF flow rates, or infections within the system. With regard to valve pressure, selection of an appropriate valve for a specific patient prior to surgery is not always a simple task. Further, an optimal valve selected at the time of implantation may no longer be appropriate given changing pathophysiological conditions as time passes. It is thus desirable to provide a single valve in which the pressure may be modified when necessary without revision. A programmable pressure valve (designed by Sophysa of France) comes in one model which accommodates different pressure settings obviating revision when pressure changes are needed. Pressure changes can be achieved externally by means of a special magnet which allows precise adjustments in valve pressure to be made through the scalp. The authors introduce the mechanism and describe the cases treated using this valve.

Adult↗
PubMed1989

[Porencephaly. Case report].

A case of porencephaly in a 33-year-old male is presented. The patient exhibited right hemiparesis and generalized seizures. Computed tomography and, subsequently, craniotomy revealed a cerebral defect in the left parietal lobe, which communicated with the lateral ventricle. On angiography and at surgery, the cortical branches of the middle cerebral artery were found to be stretched over the surface of the cyst. Histopathological examination showed the outer membrane of the cyst to consist of arachnoid, subarachnoid space, vessels, pia mater, and a layer of degenerative brain tissue on histology. The diagnosis of porencephaly and its differentiation from arachnoid cyst are discussed.

Adult↗
PubMed1989

Change in glucose metabolism with time in hydrocephalic rats.

Energy metabolism was studied by measurements of the activity and isozyme pattern of lactate dehydrogenase (LDH) in rats with kaolin-induced hydrocephalus at 1, 2, 4, and 6 weeks after the induction, as well as in normal, control rats. The total LDH activity in hydrocephalic rats was 1.5 times that in controls throughout the examination period. The main LDH isozyme in hydrocephalic rats was LDH 5(M4) at 2 weeks, but the isozyme pattern was the same as in controls at 4 and 6 weeks. These results suggest that the ratio of anaerobic to aerobic glycolysis increases in the acute stage of hydrocephalus and gradually lowers to become similar to that in controls with time.

Anaerobiosis↗
PubMed1988

An experimental study of a new sutureless intraluminal graft with an elastic ring that can attach itself to the vessel wall. A preliminary report.

A new sutureless intraluminal graft was developed with an elastic ring made of a flat spring. The diameter of the ring could be reversibly reduced by compression. The sutureless intraluminal graft with an elastic ring can attach itself to the vessel wall by elastic expansion of the ring. The elastic-ring graft was implanted in the descending thoracic aortas of nine dogs and was evaluated histologically and angiographically at different intervals from 18 to 150 days. No complication such as detachment of the ring, aortic rupture, stenosis, or aneurysmal dilatation was observed. With the new graft neither ligation nor posterior aortic wall dissection is necessary, and no anastomotic stenosis occurs. This graft is applicable even if the diameter of the aorta is small. Therefore the elastic-ring sutureless intraluminal graft promises theoretic advantages over sutureless methods that use tape ligation.

Animals↗
PubMed1988

Thoracic spinal stenosis: experience with seven cases.

The authors report seven cases of thoracic spinal stenosis caused by thickening of the laminar arch and facet joints. Claudication was a prominent clinical feature of this disorder. Motor and sensory abnormalities were found in all cases with either segmental or peripheral distribution. Diagnosis was best made from the computerized tomography scans. Treatment consisted of extensive posterior decompression including medial facetectomy, resulting in satisfactory improvement in five of the seven patients. A review of the literature regarding this disorder is presented.

Adult↗
PubMed1988

[Renal protection in acute neurosurgical diseases--effect of a low dose dopamine with reference to acute renal failure and hypernatremia in patients with dehydration].

The authors reviewed the effect of low dose dopamine administration (1-5 micrograms/kg/min) in neurosurgical patients with acute renal failure (5 cases) or hypernatremia (7 cases) in whom cerebral dehydration therapy for intracranial hypertension was thought to be causative of these disorders. Cases with hypernatremia (serum sodium over 155 mEq/l) were considered in the stage of impending acute renal failure as in the majority of cases serum creatinine levels were mildly elevated while urinary sodium was markedly diminished. Associated with systemic hypovolemia, in cases with acute renal failure (with serum creatinine over 3.5 mg/dl and urinary output of less than 20 ml/hr for more than 4 hour duration) the urinary sodium levels were less than 20 mEq/l. In all the cases treated by low dose dopamine, urinary output and sodium increased within 6 hours and in the following 24 hours stabilized urinary output with its elevated sodium (some 100 mEq/l) was obtained. As the result, elevated urea-nitrogen or serum sodium was rather easily washed out and the patients were kept adequately hydrated afterwards. Any complications such as aggravation of cerebral edema or convulsive disorder were not associated with this regime. The authors, therefore, would emphasize that low dose dopamine administration resulting in sodium diuresis and increase in renal blood flow is a practical way of method in treating patients with hypernatremia or acute renal failure caused by hyperosmolar agent infusion in their acute stage.

Acute Kidney Injury↗
PubMed1987

Dynamic changes of cerebrospinal fluid shunt flow in patient's daily life.

The shunt flow rate will be greatly influenced by the changing posture of the patient. A newly designed method of assessing shunt flow rate by isotope clearance is described and the results of phantom experiments and clinical data are presented. This method makes it possible to assess shunt flow rates in a variety of postures, such as recumbent, or head raised or as posture changes from recumbent to sitting and eventually to upright. As patients changed from the recumbent to the sitting position, shunt flow rates ceased in some cases. In cases with low flow rates in the recumbent position, shunt flow rate increased with any elevation of the upper half of the body. In many cases, flow rates increased as the patient's position changed from recumbent to sitting and then to the upright position. The results suggest that shunt flow rates vary substantially as postures alter in a patient's daily life.

Adolescent↗
PubMed1987

Spontaneous cervical epidural hematoma.

The authors report a case of spontaneous cervical epidural hematoma in a 13-year-old boy who exhibited hematoma recurrence 3 years after the first incidence. A review of the literature indicates very few reports of the recurrence of spinal epidural hematoma.

Adolescent↗
PubMed1987

[Clinical application of the central somatosensory conduction time (CCT)].

We tried to prove the usefulness of CCT as an index of cerebral functions. CCT, regional cerebral blood flow (CBF) and CT scan findings were studied in 213 neurological patients with CVD (66 cases), cerebral tumors (66 cases) and head traumas (81 cases). The technique of CCT recording was modified from that of Jones (1977) using CADWELL 5200 system. CCT was defined as the difference of the peak latency between N13 recorded at the C-7 vertebral electrode and N20 recorded at the somatosensory cortex. The control CCT in normal volunteers (N = 20) was 5.7 +/- 0.4 msec. RCBF was measured with 133 Xe intra carotid injection method of Lassen & Ingvar using gammacamera (DEC GAMM 11/34). CCT tended significantly to become more prolonged in affected hemisphere than in unaffected hemisphere of patients with three groups (CVD, tumor and trauma) (p less than 0.01). Forty percent reduction of control rCBF caused a prolongation of CCT over 7 msec. The degrees of CCT prolongations appeared to be proportional to the degree of rCBF diminution. Prolongation of CCT was remarkable in the side of low density area on CT scan. The prolongation of CCT were revealed in the patients before they did not manifest their neurological deficits especially in the disease of metastatic tumors and glioma. In the case of patients with trauma who we could follow to measure rCBF, CCT tended to become shorten as rCBF increased till normal range. CCT was not significantly prolonged in congenital hydrocephalus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1986

[Computerized single probe system using a cadmium telluride detector].

Using cadmium telluride (CdTe) as a detector, we assembled a computerized single probe system. The size of the CdTe used is 16 mm in diameter and 2 mm in thickness. Two types of the straight bore collimators of 16 mm in diameter were prepared. One is 16 mm in length (long type) and the other is 5 mm in length (short type). The response curves of the long and short type collimators to 57Co in water showed that the points at 10% of maximum counts were 4 cm and 3 cm in depth along the center axis. The data were accumulated by using a commercialized single cardiac probe system (OMNISCOPE) and processed by itself or transferred to the microcomputer (LSI-11/23) for further analysis. Twenty percent count loss occurred at 100 000 cps with an integral discriminator setting. This system was applied for cerebrospinal fluid (CSF) shunt flow evaluation and measurement of left ventricular ejection fraction (LVEF). Measurement of CSF shunt flow has been able to do in any patient's positioning. In 21 patients with various heart diseases, LVEFs obtained by CdTe detector were compared with those obtained by scintillation detector. There was good correlation between the LVEFs obtained by these two detectors: correlation coefficient (r)=0.939.

Cadmium↗