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Biomedical subjects

K Ohno

Publications and source records attributed to K Ohno.

At least 541 records · Page 30Linked to original sources
PubMed1990

Saccular aneurysms of the distal anterior cerebral artery.

We report a series of 42 consecutive patients with aneurysms of the distal anterior cerebral artery (ACA). Of these, 36 patients had one aneurysm, 5 had two aneurysms, and one had three aneurysms. Thirty patients had a ruptured distal ACA aneurysm; among these patients, the size of the aneurysm was less than 5 mm in diameter in 20, 6 to 10 mm in 7, and larger than 11 mm in 3. Eighteen patients (42.9%) had multiple aneurysms, and distal ACA aneurysms were responsible for a subarachnoid hemorrhage in 10. Thirty-four patients underwent direct surgery, and 30 of these had excellent outcomes 3 months after surgery. The treatment of patients with distal ACA aneurysms is often technically difficult, because of their broad neck configuration and the coexistence of other aneurysms. Nevertheless, the present study emphasizes that distal ACA aneurysms tend to bleed, irrespective of their size, and that excellent outcomes are obtainable by direct surgery.

Adult↗
PubMed1990

Lysosulfatide (sulfogalactosylsphingosine) accumulation in tissues from patients with metachromatic leukodystrophy.

We describe here a sensitive assay method for lysosulfatide (sulfogalactosylsphingosine) in human tissues using HPLC. The method involves extraction of lipids, saponification, isolation using a C18 Sep-Pak column, derivatization with o-phthalaldehyde, and detection of the fluorescent lysosulfatide using HPLC. In control subjects, a small amount of lysosulfatide was detected in the cerebral white matter (9-35 pmol/mg of protein), spinal cord (35 pmol/mg of protein), sciatic nerve (14 pmol/mg of protein), and kidney (approximately 2 pmol/mg of protein) but not in the cerebral gray matter and liver. A marked accumulation of the lipid was noted in tissues from six patients with metachromatic leukodystrophy (MLD). The concentration of lysosulfatide was high in the cerebral white matter, spinal cord, and sciatic nerve (223-1,172 pmol/mg of protein). Even in the cerebral gray matter, kidney, and liver, where lysosulfatide was hardly detected in the control sample, a considerable amount (3-45 pmol/mg of protein) accumulated in MLD patients. The concentration and distribution pattern of lysosulfatide were similar to those of galactosylsphingosine (psychosine) accumulated in patients with Krabbe disease. Therefore, the accumulation of lysosulfatide may explain the demyelination in patients with MLD, as is the case with Krabbe disease.

Cerebroside-Sulfatase↗
PubMed1990

Carteolol is a useful tool to prove the tonically functioning nature of presynaptic beta-adrenoceptors on peripheral noradrenergic neurons but not on central catecholaminergic neurons.

Effects of carteolol on norepinephrine (NE) release were studied at 2 Hz mainly in rat hypothalamic slices. Isoproterenol at 1 and 10 nM concentration-dependently facilitated NE release. Isoproterenol (10 nM)-induced facilitation was antagonized by 1 and 10 nM dl-carteolol, but not antagonized by 1 nM d-carteolol. dl-Carteolol alone at 1 nM to 10 microM did not inhibit NE release. In brainstem slices, 10 nM isoproterenol also facilitated NE release, and this facilitation tended to be antagonized by 1 nM dl-carteolol. Nanomolar concentrations of carteolol stereoselectively antagonized isoproterenol-induced facilitation of NE release via presynaptic beta-adrenoceptors in rat hypothalamic slices.

Adrenergic beta-Antagonists↗
PubMed1990

[Breeding of cataract rat strain (ICRF/Kmu//Yg)].

A inbred strain, ICRF, which can be used as a model of both human cataract and epilepsy is described. The strain was bred from the ICR cataractous rat (Ihara, 1983). The original ICR strain showed bilateral cataract on 11-12 weeks of age, but the cataractous syndrome frequently disappeared during life. In the new ICRF strain the cataractous syndrome continued through the life, as shown by primary investigation of 38 males and 32 females. Besides cataract, severe epilepsy-like seizures were observed in 90% of the males. Seizures were rare in females (3%). The life span of the ICRF rats was short, 58% of the males and 6% of the females died before 52 weeks of age.

Animals↗
PubMed1990

Morphological relationships between osteoclasts and bone resorption surfaces on mouse parietal bones.

Parietal bones from mice 1-20 weeks of age were histochemically stained for detection of acid-phosphatase activity and then observed by the light microscope to evaluate the distribution and shape of osteoclasts on the inner surface of their bones. After microscopic examination, the same bones were macerated by NaOCl to both remove organic materials and expose the mineralized surface. The inner surface was then examined by scanning electron microscopy and the observations were compared with the light micrographs of the areas where osteoclasts were located. The bone resorption areas were identified as well-demarcated rough areas, and corresponded to the areas where osteoclasts were distributed. In young mice, osteoclasts observed in the bone resorption areas, which were composed of accumulations of irregular concavities, were mainly polygonal or round in shape. In adult mice, elongated osteoclasts with longer or shorter cytoplasmic processes were predominant; the bone concavities were also elongated and gathered in a flame-like pattern. The findings suggest that osteoclasts change shape according to their resorptive activities and that the activities differ between growing bones and those where growth has ceased, probably in relation to the modeling and remodeling of the bone.

Acid Phosphatase↗
PubMed1990

[A study on reduction rate of tumor volume by irradiation in germinoma, malignant lymphoma, and medulloblastoma].

A relationship between radiation dose and reduction rate of tumor volume was studied in 10 patients with germinoma, nine with malignant lymphoma, and seven with medulloblastoma, in order to evaluate the effect of irradiation on these tumors. Germinomas showed either mono- or biphasic reduction of the volume with increased radiation dose in semi-logarithmic expression, irrespective of their size. All patients are well without relapse except for one that was lost because of transfer. The reduction rate of tumor volume was slightly less in malignant lymphomas and medulloblastomas than that in germinomas and the former two showed less uniformity of response to irradiation according to each case. Malignant lymphomas tended to regrow during irradiation period or early after the period and the effect of irradiation seemed to be related to the size of the tumor. Medulloblastomas did not completely disappeared during irradiation period, but delayed effect of irradiation was recognized after the period.

Adolescent↗
PubMed1990

[A study of an autosomal recessive polycystic kidney disease with facial and skeletal abnormalities in rat].

Clinico-pathological studies were made on rats with polycystic kidney disease (PCK), a congenital renal disorder transmitted as an autosomal recessive trait and characterised by facial and skeletal anomalies, with the results summarised as follows: 1) Affected animals had a poor weight gain and slightly increased urinary excretion of low molecular weight protein from 2 months after birth, and developed polyuria and hypocalciuria 5 months postnatally. They had elevation of serum urea nitrogen, increased urinary excretion of urea nitrogen and hypoproteinemia 8 months postnatally though without showing elevated serum creatinine and died around 10 months of life. 2) Kidneys of chin rats appear granular in surface, enlarge little by little while preserving the entire kidney morphology; a small cyst is formed in the renal medulla 2 months postnatally, then enlarges gradually to encroach upon the cortex and grows to involve all cortical layers by 8 months of life. This cyst was revealed by lectin staining to be derived from the collecting ducts and was assumed to correspond, both morphologically and clinically, to the infantile or juvenile form of PCK in humans. Pathogenetic factors of the characteristic facies and skeletal abnormalities were also investigated.

Animals↗
PubMed1990

GM2-gangliosidosis B1 variant: analysis of beta-hexosaminidase alpha gene abnormalities in seven patients.

A single nucleotide transition within exon 5 of the beta-hexosaminidase alpha chain gene was identified in a Puerto Rican patient with GM2-gangliosidosis B1 variant as the mutation responsible for the unusual enzymological characteristics of this variant (G533----A; Arg178----His) (the DN-allele). A total of seven patients with enzymological characteristics of B1 variant have since been studied. They were Puerto Rican (DN), Italian, French, Spanish, two patients of mixed ethnic origin (English/Italian/Hungarian and English/French/Azores), and a Czechoslovakian. In confirmation of our earlier finding based on screening with allele-specific probes, all patients except the one from Czechoslovakia carried the same DN-allele. A new point mutation found in this patient changed the same codon affected in the DN-allele (C532----T; Arg178----Cys). An asymptomatic Japanese individual included as a control also carried one allele with the DN-mutation. Site-directed mutagenesis and expression studies in COS I cells demonstrated that either of the two point mutations abolishes the catalytic activity of the alpha subunit. The Spanish patient was homozygous for the DN-allele, but others were all compound heterozygotes. The Puerto Rican patient was a compound heterozygote with the DN-mutation in one allele and with the four-base insertion in exon 11, one of the two mutations found in the classical Ashkenazi Jewish Tay-Sachs disease, in the other allele. Abnormalities of the other allele were not identified in all other compound heterozygous patients. In these patients, the level of mRNA derived from the other allele was variable, ranging from being undetectable to being much lower than normal. This series of studies uncovered a new B1 variant mutation, confirmed our preliminary finding that the DN-allele has a surprisingly wide geographic and ethnic distribution, and pointed out the highly complex nature of the molecular genetics of this rare disorder. They also support our working hypothesis that mutations responsible for the unique enzymological characteristics of the B1 variant should be located in or near exon 5 of the gene and that this region of the enzyme protein is critical for its catalytic function.

Alleles↗
PubMed1990

[Intrapericardial bronchogenic cyst--a report of two surgical cases].

Two cases of intrapericardial bronchogenic cyst are reported. Case 1 was a 58-year-old man with a complaint of exertional dyspnea. A chest X-ray film showed a right hilar mass shadow. Echocardiographically the mass showed cystic pattern in the pericardium. A pulmonary angiogram revealed a mass displacing the right pulmonary artery superiolaterally and left atrium and pulmonary vein inferiorly. The preoperative diagnosis was intrapericardial cyst. Subtotal resection of intrapericardial cyst was performed via right thoracotomy. Histological diagnosis was bronchogenic cyst. The postoperative course was uneventful. Case 2 was a 41-year-old man. A displacement of the esophagus and duodenal ulcer was pointed out in the upper gastrointestinal series. A chest X-ray film showed a right hilar mass shadow. Since echocardiogram and pulmonary angiogram revealed similar findings to those in case 1, intrapericardial bronchogenic cyst was suspected preoperatively. Complete resection of the intrapericardial cyst was made via right thoracotomy. Histological diagnosis was bronchogenic cyst. The postoperative course was uneventful.

Adult↗
PubMed1990

[A case of intralobar pulmonary sequestration associated with abnormal connection between the aberrant artery and the pulmonary artery].

The patient was a 5-year-old girl and had a history of recurrent pneumonia. Angiogram demonstrated that the aberrant arteries arising from descending aorta communicated with left pulmonary A10 where the multi-lobulated cystic lesion was seen by chest X-P. The right heart catheterization revealed the step-up of oxygen saturation in distal part of left pulmonary artery A10. Diagnosis was the intralobar pulmonary sequestration with the aberrant arteries communicating with pulmonary artery. The connection between aberrant arteries and pulmonary artery in this case might be caused by the chronic inflammation in the sequestrated lung. We found 4 case reports in which the communication between aberrant arteries and pulmonary artery was evident.

Aortography↗
PubMed1990

[Non-Hodgkin's lymphoma arising from the wall of old tuberculous empyema--a surgical case report].

A 71-year-old male underwent therapeutic pneumothorax for left pulmonary tuberculosis 42 years ago. He visited our hospital in February 1988 with a complaint of hemosputum. In October, cytology of sputum revealed malignant cells, and the patient was admitted to our hospital for further examination. Because malignant cells were found by the left bronchial lavage, pan-pleuropneumonectomy was performed on January 12, 1989 under the diagnosis of left lung cancer. The tumor was partially left unremoved. Histological diagnosis was diffuse large cell type, B cell non-Hodgkin's lymphoma. Postoperatively, 2 courses of cyclophosphamide, adriamycin, vincristine, prednisone, etoposide (CHOP and VP-16) therapy were performed. However, the patient died of respiratory insufficiency on the 125th postoperative day. Recently, cases of malignant lymphoma involving the pleura after the old tuberculous empyema and therapeutic pneumothorax have been increased. Therefore, prompt diagnosis and treatment are recommended when tumor shadow is suspected as a result of imaging examination.

Aged↗
PubMed1990

[Experimental studies on extracorporeal membrane oxygenation (ECMO) perfusion for respiratory insufficiency associated with pulmonary hypertension].

Some types of neonatal respiratory insufficiency may be associated with severe pulmonary hypertension. This paper evaluates two methodologies of ECMO perfusion in the treatment of such serious respiratory insufficiency. Pulmonary hypertension was prepared in dogs by administering small pieces of gelatin sponge into the main pulmonary artery. The two methodologies of perfusion were venoarterial bypass (VAB) and venovenous bypass (VVB). Prior to ECMO perfusion, oxygen supplementation during perfusion and hemodynamics were examined. Oxygen supplementation was satisfactory in both VAB and VVB. With VAB, the mean pulmonary artery pressure (mPAP) was significantly dropped from 33.8 +/- 3.1 mmHg to 28.4 +/- 6.2 mmHg, the pulmonary blood flow (PBF) being significantly declined from 1.39 +/- 0.21 L/min to 1.07 +/- 0.15 L/min. With VVB, mPAP was significantly dropped from 33.9 +/- 6.2 mmHg to 29.1 +/- 5.1 mmHg, the pulmonary vascular resistance (PVR) being significantly decreased from 1983.1 +/- 656.0 dynes.sec.cm-5 to 1740.4 +/- 635.9 dynes.sec.cm-5. It is considered that VAB renders PBF decline, which induces a drop in PAP, while VVB accelerates a flow of well-oxygenated blood in the pulmonary artery, which results in a decline in PVR and then a drop in PAP. VVB as well as VAB is useful in the treatment of neonates with respiratory insufficiency who present with pulmonary hypertension.

Animals↗
PubMed1990

[Gore-Tex grafts for replacement of the superior vena cava in 10 patients with intrathoracic malignant tumors].

Ten patients with lung cancer and mediastinal tumor invading the mediastinal structures underwent replacement of superior vena cava (SVC) with ringed Gore-Tex to resect malignant tumors. In patients with lung cancer sleeve pneumonectomy (3 patients), sleeve lobectomy (1 patients) and tracheal resection (one patient) were performed simultaneously. By resection of the VCS system, invasive thymomas were able to be resected completely in 2 of 3 patients. In 2 patients with mediastinal tumors, one with metastatic testicular chorio carcinoma and one with malignant lymphoma of non-Hodgkin type, aggressive chemotherapy was followed by resection of the residual tumors including VCS. Except for one patient, there was no sign showing disturbance of the venous return in the VCS system in the 5 to 43 months' postoperative follow up period. We conclude that ringed Gore-Tex graft permits the extended operation for intrathoracic malignancies invading the mediastinal structures.

Adenocarcinoma↗
PubMed1990

[A case of type C Niemann-Pick disease].

We diagnosed a 3-year-old boy as type C Niemann-Pick disease by studies on cultured fibroblasts; sphingomyelinase activity was almost normal, but esterification of exogenously administered cholesterol was deficient. Also sparse cultures of his fibroblasts developed a relatively intense fluorescence with filipin that was not observed either in normal or type B Niemann-Pick fibroblasts. We tried to treat him with dimethylsulfoxide (DMSO), 100 mg-120 mg/day for a year, but it had clinically insufficient effect on our case.

Child, Preschool↗
PubMed1990

[A case of ventricular septal defect with tricuspid regurgitation complicating infective endocarditis].

A unique case of 52-year-old woman with a ventricular septal defect associated with tricuspid regurgitation complicating infective endocarditis was reported. Under cardiopulmonary bypass, the VSD was closed directly and tricuspid valve was replaced with a Carpentier-Edwards valve. Intraoperative examination showed that the VSD was perimembranous type (5 mm in diameter), all three leaflets were destroyed and one chordae of anterior leaflet was ruptured. Her postoperative course was uneventful and she has been well.

Cardiopulmonary Bypass↗
PubMed1989

[Effectiveness of pharmacoangiography using nitroglycerin and angiotensin II].

An investigation of pharmacoangiography using a combination of nitroglycerin and angiotensin II demonstrated that it was useful due to the following reasons. First, good dilatation of the proximal portion of the arteries was demonstrated which enabled good clarity of the margin between the encasement and the normal portion of the arteries. Secondly, there was almost no change demonstrated in blood pressure immediately after administration. Thirdly, tumor vessels and intrapancreatic arteries were well recognized on the resulting images.

Angiography↗
PubMed1989

Specific amplification of deleted mitochondrial DNA from a myopathic patient and analysis of deleted region with S1 nuclease.

Heteroplasmy of the normal-sized and the deleted mitochondrial genome has been observed in mitochondrial myopathy. The deleted region of the genome in the skeletal muscle of a patient was analyzed both by the conventional Southern blot method and by the novel method of employing the combination of polymerase chain reaction and S1 nuclease digestion. The results obtained by these methods were compared. Southern hybridization using various mitochondrial DNA fragments localized the deletion from at least position 9020 to 14,955, but regions of uncertainty of 1 kb remained on both ends of the deletion. Using the polymerase chain reaction, a fragment from the deleted genome was specifically amplified by choosing a pair of primers surrounding the deletion, and two fragments adjacent to the starting and end of the deletion were amplified from the normal-sized genome. S1 nuclease analysis of the heteroduplexes formed among these fragments demonstrated that the deletion extended from positions 8650 +/- 50 to 15,660 +/- 60. This method does not require radioisotopes and, moreover, can determine the deleted region within 5 h, in contrast to the 2 days required by the conventional Southern blot analysis. These results indicate that the novel method is faster and more accurate than the conventional method for the determination of the deleted region of genome.

Adult↗