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Biomedical subjects

M Maruno

Publications and source records attributed to M Maruno.

At least 55 records · Page 3Linked to original sources
PubMed1998

Spatial perception in macroscopic and microscopic surgical manipulations: differences between experienced and inexperienced surgeons.

The spatial perceptions of the phantom surgical field with the naked eye and under the surgical microscope were analyzed in a group of experienced and a group of inexperienced neurosurgeons. The phantom surgical field contained a start point, a virtual gate, and a target point. The virtual gate was an invisible zone arbitrarily set in the phantom surgical field. The examinees were first instructed regarding the position of the invisible virtual gate. Then they were asked to point consecutively to the three points with a suction tube under three different circumstances: with the naked eye, under the microscope, and by watching a navigation monitor. A surgical navigator was used to record the three-dimensional position of the suction tip. The pointing deviation from the suction tip to the center of the virtual gate was evaluated. The pointing accuracy with the naked eye did not differ between the two groups, but that under the microscope was significantly better in the experienced group than in the inexperienced group. Fluctuations in pointing deviation were significantly greater in the inexperienced neurosurgeons, especially with the microscope. Further analysis demonstrated that these differences were attributable to poorer depth perception of the phantom surgical space among the inexperienced neurosurgeons.

Clinical Competence↗
PubMed1998

A peritoneal marker for optimal timing of ventriculo-peritoneal shunt revision in early childhood.

The ventriculo-peritoneal shunt placed in a neonate or infant needs revision to lengthen the peritoneal tube at certain times during childhood. The critical time for this revision is not exactly the same between individuals. Furthermore, the level of peritoneal insertion of the shunt tube is often unclear on x-ray films. To plan for and determine the optimal timing of revision, we applied a titanium clip on the peritoneal suture line in three infants as a marker of peritoneal insertion level. During the 31- to 37-month follow-up period, abdominal x-ray clearly demonstrated the peritoneal insertion level in all three patients, allowing accurate determination of the length of the intraperitoneal portion (i.p.) of the shunt tube. The rate of shortening of the length of i.p was 20 to 27% of the increase in body height (BH). This technique allows accurate determination of the length of i.p. and also optimal timing for revision.

Body Height↗
PubMed1998

Translucence stereoscopy of interictal magnetoencephalographic epileptiform discharge.

We have developed a translucence stereoscopy method for displaying the distribution of multiple interictal epileptiform discharges within the intracranial space. The epileptiform discharges, measured using a whole-head magnetoencephalography system, were modeled by a least-squares method to obtain the equivalent current dipoles. The dipoles were located in the stereo pair of intracranial images composed of translucent brain slices at several selected levels. The technique demonstrated clearly the distribution of interictal dipoles within the brain in three patients. Three dimensional understanding of the intracranial distribution of multiple dipoles in one image is valuable in analyzing the intracerebral neurophysiological events in epileptic patients.

Adult↗
PubMed1998

Chromosomal losses and gains in meningiomas: comparative genomic hybridization (CGH) study of the whole genome.

We investigated chromosomal aberrations in meningiomas using newly developed comparative genomic hybridization (CGH) technique and compared the results with the proliferating potential of the tumors. This technique permits the entire genome to be surveyed in one session of experiments. Our results revealed chromosomal aberrations in 5 out of 10 (50%) of the tumor samples studied. Losses of the distal parts of chromosome 1p (5 out of 10) and 22q (3 out of 10) were the two most frequent chromosomal aberrations. Losses and/or gains in other regions were only sporadic. The MIB-1 staining indices (MIB-SI, %) were 1.9 +/- 0.9% (mean +/- SD) in benign (n = 8), 4.5% in atypical (n = 1), and 11.7% in anaplastic (n = 1) meningiomas. The comparison of MIB-SI between the tumors with (2.3 +/- 0.6%) and without (1.6 +/- 0.3%) chromosomal aberrations demonstrated a trend towards an increased MIB-SI in meningiomas with chromosomal aberrations (p < 0.07) by unpaired Student's t-test. This study suggests that alterations in chromosomes 1p and 22q could be a primary focus of further detailed assessment of tumorigenesis and in understanding the biological behavior of meningiomas.

Adolescent↗
PubMed1998

Mobile fluoroscopic open stereotaxy for MRI-negative angiographic microlesions.

The approach to the deep-seated angiographic microlesion is often difficult, particularly when it is not demonstrated by computed tomography (CT) or magnetic resonance imaging (MRI). We have developed a method to localize these lesions for open stereotactic surgery employing mobile fluoroscopy. Prior to craniotomy, the patient's head is fixed in a stereotactic frame in a position optimal for the routine microscopic surgery. Following the injection of contrast media, the location of the lesion is marked on the fluoroscope monitor. Under fluoroscopic control, the scalp is marked using radiopaque pointer on each side of the patient's head so that the scalp marks and the target lesion overlap each other on the fluoroscope monitor. Thus the imaginary line connecting these scalp marks passes through the lesion. An additional pair of scalp marks is obtained by changing the projection angle of the fluoroscope. By simple calculation, the coordinates of the lesion are obtained as the nearest point to these two imaginary lines, each of which connects a pair of scalp marks. After craniotomy, the lesion is approached using an open stereotactic technique. The first patient had an aneurysm 1.5 mm in diameter that arose from the feeder of the arteriovenous malformation. The second patient had a small residual nidus of arteriovenous malformation 1.5 cm in diameter in the deep frontal lobe, not recognizable by CT or MRI because of artifacts from a previous surgery. Both patients were successfully operated by employing the present method. This method requires only a conventional stereotactic frame and a mobile fluoroscope, and provides simple and reliable localization of the small lesions recognizable only by cerebral angiography.

Arteriovenous Malformations↗
PubMed1998

Direct ethanol injection for skull metastasis from hepatocellular carcinoma. The techniques and consequences of a therapeutic trial.

The frequency of skull metastasis from hepatocellular carcinoma (HCC) is increasing together with the recent progress in the management of the primary lesion. Cases are often complicated with poor general conditions or metastasis to the other organs, and not readily indicated for surgery. A direct injection of ethanol to the lesion could be one of the therapeutic options to cope with this complicated situation. To evaluate the feasibility of this technique, we planned a therapeutic trial in a patient with HCC associated with lumbar and skull metastasis, the latter metastasis repeated twice during the past one year. A total of 10 ml of ethanol was injected into the skull metastasis percutaneously under ultrasound (US) guidance. US guidance was very useful in determining the sites of injections and the distribution of ethanol as well as monitoring the blood flow within the tumor vessels. The patient transiently complained of local pain at the injection sites, but there were no other adverse effects. Four days after the injection, the lesion was resected by surgery, which confirmed the pathologic diagnosis as well as the nearly-total necrosis of the tumor. This technique is simple, safe and repeatable with low cost. The technical details and the histologic effects are described.

Aged↗
PubMed1998

A preliminary study aimed at the detection of Leishmania parasites in subjects with cutaneous leishmaniasis using polymerase chain reaction.

As a basic study for future diagnosis of cutaneous leishmaniasis, we tried to detect Leishmania parasites representing different species in the subgenera Leishmania and Viannia from subject patients with cutaneous leishmaniasis by using the polymerase chain reaction (PCR) with the subgenus Viannia specific primer. Four out of the 14 specimens revealed an amplified DNA of 70 bp specific for the subgenus Viannia (L. braziliensis complex). No bands were detected in the rest of the specimens belonging to the subgenus Leishmania and unclassified groups. The base sequences of the amplified DNA corresponded with those of the L. (V). braziliensis kinetoplast minicircle. We concluded that PCR using the present primer specific for the subgenus Viannia would be useful in detecting Leishmania parasites in lesions of cutaneous leishmaniasis caused by the L. braziliensis complex.

Animals↗
PubMed1998

Comparative studies of the detection rates of Leishmania parasites from formalin, ethanol-fixed, frozen human skin specimens by polymerase chain reaction and Southern blotting.

In this study, detection rates of Leishmania parasites from human skin were compared among three different types of specimens, formalin-fixed, ethanol-fixed, and frozen, by polymerase chain reaction (PCR) and Southern blotting. For this purpose, we used biopsy specimens collected from 19 leishmaniasis patients and performed PCR and Southern hybridization with the probe specific for Leishmania (Viannia) braziliensis complex. Among these 19, 16 specimens were from cutaneous leishmaniasis (CL), one, diffuse cutaneous leishmaniasis (DCL) and 2, mucocutaneous leishmaniasis (MCL) and were formalin-fixed and paraffin-embedded. The causative agents for one case of CL and one case of DCL were already identified as L. (Leishmania) complex. Six specimens of CL were preserved in 100% ethanol. Two specimens of MCL were frozen tissues. PCR using the formalin-fixed and paraffin-embedded specimens revealed positive bands at 70 bp in 9 (47.4%) out of 19 specimens of CL, MCL and DCL. Southern blotting detected the signals in 12 (63.2%) out of the 19. PCR using the 100% ethanol-fixed specimens revealed positive bands in 4 (66.7%) out of 6, and Southern blotting also detected the signals in 4 (66.7%) out of the 6. PCR and Southern blotting using 2 frozen specimens of MCL were always positive (100%). Although we failed to detect significant differences by Chi-square test between the results from the formalin-fixed, paraffin-embedded specimens and those from 100% ethanol-fixed ones, we concluded that ethanol-fixed specimens, convenient for transportation and storage, would be more useful for diagnosis of leishmaniasis by PCR in a developing country.

Adolescent↗
PubMed1997

Effect of byakko-ka-ninjin-to on the efferent activity of the autonomic nerve fibers innervating the sublingual gland of the rat.

The effect of intraduodenal infusion of Byakko-ka-ninjin-to (BN) on the efferent activity of the autonomic outflow to the sublingual gland was observed in the anesthetized rat. Intraduodenal infusion of BN (50-200 mg/kg) resulted in a dose-related increase in efferent activity. The enhancement of the nerve activity following administration of 200 mg/kg BN lasted longer than three hours. It was observed that the suppressive effect on efferent activity due to i.v. administration of hypertonic saline was antagonized by intraduodenal infusion of BN. From these observations it is suggested that Byakko-ka-ninjin-to acts as a facilitatory agent on salivary secretion.

Adrenergic alpha-Agonists↗
PubMed1997

A case of giant cell reparative granuloma of the petrous bone: demonstration of the proliferative component.

BACKGROUND: Giant cell reparative granuloma (GCRG) is an uncommon benign lesion of the bone. It typically arises in the mandible and rarely involves the skull. The cytologic nature and genesis of the involved cells are poorly understood. METHODS AND RESULTS: We report a case of GCRG in the petrous bone of a 3-year-old girl. One year following gross total removal, the granuloma recurred locally and was resected en bloc at the second surgery. Histologically, the lesion was composed of oval or spindle-shaped stroma cells admixed with a number of multinucleated giant cells. Immunohistochemical study demonstrated that 5.6% of the stroma cells, but none of the multinucleated giant cells, were positive for MIB-1 antibody. CONCLUSION: These results suggest that this lesion expands by proliferation of the stromal component, with a growth rate roughly between those of the typical benign and malignant brain tumors. The cytologic nature of the cells comprising this uncommon disease remains to be elucidated.

Child, Preschool↗
PubMed1997

Topical application of fibrin adhesive in the rat brain: effects on different cellular elements of the wound.

Although fibrin adhesives are popular in the field of neurosurgery, the medical literature is devoid of study elucidating their effects on the brain tissue. To study the safety of applying fibrin glue to the brain and to explore new surgical potentialities, we implanted soft pellets made of fibrin glue into the brains of Wistar rat. Following 6 h and 3, 7 and 14 days post-implantation survival, the brains were removed and paraffin sections were processed for hematoxylin-eosin staining, as well as immunohistochemistry for microtubule-associated protein (MAP-1A) and glial fibrillary acidic protein. The changes in the neuronal and glial elements and also the numbers of inflammatory and endothelial cells in the vicinity of implanted fibrin glue pellets were compared with those of gelfilm pellets. The results demonstrated that topical application of fibrin glue to the brain causes significantly enhanced local accumulation of mononuclear cells and promoted angiogenesis close to the wound while not affecting the neuronal and glial elements. These findings suggest that fibrin glue can be considered as a safe supportive material for intradural procedures directly involving the brain tissue.

Adhesives↗
PubMed1997

In-vivo assessment of extrahepatic metabolism of paeoniflorin in rats: relevance to intestinal floral metabolism.

The extraction ratios of paeoniflorin in gut wall (EG), liver (EH) and lung (EL) were assessed by comparing AUCs after various routes of its administration to estimate the first-pass effects and the metabolism by intestinal flora. Pulmonary extraction ratio of paeniflorin was assessed by comparing AUCs calculated from venous and arterial plasma concentrations after its intravenous administration (0.5 mg kg-1). The mean pulmonary extraction ratio was estimated to be 0.06. The hepatic extraction ratio (EH was assessed by comparing AUCs after intraportal and intravenous administrations (0.5 and 5 mg kg-1). The plasma concentration profiles of paeoniflorin after intraportal administration were very close to those after intravenous administration, suggesting a negligible hepatic extraction ratio of paeoniflorin. The AUC value after intraperitoneal administration (0.5 mg kg-1) was greater than that after intraportal or intravenous administration. This finding suggests that paeoniflorin is not metabolized in the gut wall. The transference of paeoniflorin from the serosal side to the mucosal side was evaluated by the in-vitro everted sac method. The low intestinal permeability (19.4% at 60 min) was demonstrated by the comparison with phenobarbital (63.1% at 60 min). We conclude that paeoniflorin is not metabolize by gut wall, liver and lung, its poor absorption from the intestine results in extremely low bioavailability and the unabsorbed fraction of paeoniflorin is degraded by the intestinal flora.

Animals↗
PubMed1997

Distribution of endogenous tumour necrosis factor alpha in gliomas.

AIMS: To determine the distribution and cellular origin of endogenous tumour necrosis factor alpha (TNF alpha) in the cellular components of human gliomas. METHODS: Frozen sections of 26 gliomas (four astrocytomas (As); two oligoastrocytomas (OA); one ansplastic astrocytoma (AA); one anaplastic oligoastrocytoma (AOA); 18 glioblastomas (GB)) were examined immunohistochemically using antihuman TNF alpha and anti-Leu-M5 (CD11c) antibodies. Additional studies with double immunohistocchemical procedures were performed with anti-glial fibrillary acidic protein and anti-neurofilament antibodies. RESULTS: Eighty per cent of the AA, AOA, and GB (16 of 20) had a positive reaction for TNF alpha, but only 17% of As and OA (one of six) were positive. Positive cells were seen in both the tumour tissue and adjacent brain tissues. TNF alpha protein was detected not only in the tumour cells but also in the endothelium of tumour vessels as well as reactive astrocytes and neurons. CONCLUSIONS: Endogenous TNF alpha is present in cells of various origins in glial tumours including tumour vessels; however, the role of TNF alpha may be different in different types of cells or altered microenvironment.

Brain Chemistry↗
PubMed1997

Chromosome 22q allelic losses at microsatellite loci in human astrocytic tumors.

Common regions of deletion(s) on chromosome 22q and the correlations between loss of heterozygosity and patient survival were analysed in 18 deoxyribonucleic acid samples from astrocytic tumors (3 astrocytomas, 5 anaplastic astrocytomas, and 11 glioblastomas) and matched normal brain tissues. The polymerase chain reaction products using five microsatellite markers were electrophoresed on polyacrylamide gels and the ethidium bromide stained bands were photographed. Loss of heterozygosity was observed in 14 (74%) of 19 samples, with similar incidences in astrocytomas, anaplastic astrocytomas, and glioblastomas (67%, 80%, and 82%, respectively). The locus D22S300 (q12.1-q13.1) was most frequently involved, with loss of heterozygosity in eight (80%) of 10 informative glioblastomas at this locus. Increased loss of heterozygosity during tumor progression or recurrence was seen in two patients at the D22S300 (q12.1-q13.1) and TOP1P2 (q11.2-q13.1) loci. No correlation between loss of heterozygosity on chromosome 22 and the postoperative survival was found. These findings suggest that loss of heterozygosity on chromosome 22q probably occurs quite frequently in astrocytic tumors. The chromosome segment 22q12.1-q13.1, around the D22S300 locus, may be the common region of deletion in glioblastomas.

Adult↗
PubMed1997

Single solitary metastasis of the slowly progressive type of renal cell carcinoma to the choroid plexus--case report.

A 68-year-old male developed a solitary metastasis in the choroid plexus of the right lateral ventricle 7 years after left nephrectomy for renal cell carcinoma. The lesion was totally removed and the patient has been free from recurrence for 30 months postoperatively. Pure solitary metastasis to the choroid plexus is very rare, but five of the 15 cases originated from renal cell carcinoma. There may be a link between this type of metastasis and the slowly progressive type of renal cell carcinoma.

Aged↗
PubMed1996

Antiarrhythmic effects of an aconitine-like compound, TJN-505, on canine arrhythmia models.

We examined the effects of an aconitine-like compound, TJN-505 (1alpha-16beta-dimethoxy-20-ethyl-14alpha-(4-methox ybenzoyloxy)-aconitan-8,13-diol hydrochloride), on canine arrhythmias provoked by digitalis, two-stage coronary ligation, adrenaline, programmed electrical stimulation, or aconitine. TJN-505 (2-2.5 mg/kg i.v.) suppressed digitalis-, two-stage coronary ligation- and adrenaline-induced ventricular arrhythmias. The antiarrhythmic plasma concentrations (IC50) of TJN-505 for these arrhythmia models were 1.26, 0.94 and 1.31 microg/ml, respectively. TJN-505 (2 mg/kg i.v. followed by the infusion of 0.1 mg/kg per min) prolonged PR, QRS, QTc and JTc intervals and the ventricular effective refractory period and reduced the incidence of programmed electrical stimulation-induced arrhythmias in dogs with 7-day-old myocardial infarction (P < 0.05). TJN-505 (2 mg/kg i.v.) also suppressed the aconitine-induced atrial arrhythmias. In conclusion, TJN-505 suppressed various canine ventricular and atrial arrhythmias and seems to act as a blocker of multiple channels.

Aconitine↗
PubMed1996

Loss of heterozygosity of microsatellite loci on chromosome 9p in astrocytic tumors and its prognostic implications.

We analyzed 19 samples of various astrocytic tumors (3 astrocytomas, 5 anaplastic astrocytomas, and 11 glioblastomas) for loss of heterozygosity (LOH) on chromosome 9p at 6 microsatellite loci (D9S54, IFNA, D9S171, D9S104, D9S165, and D9S166). Polymerase chain reaction was performed and the products were electrophoresed on polyacrylamide gel. As many as 16 of the 19 samples (84%) exhibited LOH. Three of the 7 informative loci (43%) showed LOH at D9S54, 7 of 17 (41%) at IFNA, 8 of 14 (57%) at D9S171, 7 of 14 (50%) at D9S104, 4 of 8 (50%) at D9S165, and 2 of 7 (29%) at D9S166. LOH was recognized in 57% of the informative loci in anaplastic astrocytomas and 54% in glioblastomas, while it was seen in only 8% of the astrocytomas. Accumulation of LOH with progression or recurrence of tumor was seen in 2 patients. Although, the survival period of the patients correlated well to the histological types of astrocytic tumors, we could not find any obvious correlations between the presence/absence of LOH and the survival period in these patients. In conclusion, we speculate that LOH on chromosome 9p is involved in malignant progression of astrocytomas, but has no significance in predicting survival period in these patients.

Adult↗