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Biomedical subjects

T Ohashi

Publications and source records attributed to T Ohashi.

At least 217 records · Page 12Linked to original sources

Transduction of CD34+ enriched cord blood and Gaucher bone marrow cells by a retroviral vector carrying the glucocerebrosidase gene.

One promising strategy for gene therapy of Gaucher disease involves ex vivo retroviral transduction of autologous hematopoietic stem cells. Studies in small animals have demonstrated that this approach provides a life-long supply of the glucocerebrosidase (GC) enzyme. Human application has developed to the stage of a clinical trial. In this study, we describe development of a high titer amphotropic producer line for the vector, MFG-GC, and explore transduction of CD34+ cells from various human sources. Higher than three times the normal levels of glucocerebrosidase activity in non-transduced cells were achieved following transduction of CD34+ cells obtained from bone marrow or cord blood from normal donors. The improvement in enzyme activity in Gaucher marrow was about 40-fold above deficient levels. We examined the timing and stepwise effect of multiple rounds of infection and evaluated post-infection expansion of cells in two different cytokine mixtures. Transduction efficiency was determined using immunocytochemistry and Southern blot hybridization.

Antigens, CD34↗

[A case of isolated vagus nerve palsy with herpes zoster].

A case of isolated vagus nerve palsy with herpes zoster was reported. A 31-year-old woman was admitted to our hospital with six days' history of difficulty of swallowing of fluid and hoarseness with a painful vesicle on the right ear. Neurological examination revealed poor elevation of soft palate on the right side, but the pharyngeal reflex was preserved. Herpetic vesicles were present on the right concha, within posterior wall of the external auditory meatus. No facial palsy, loss of hearing and mucosal lesions in the mouth or pharynx were present. This is the first case of isolated vagus nerve palsy due to varicella-zoster infection, showing the distribution of the auricular branch of the vagus (Arnold's nerve) in the ear.

Adult↗

[Visual function in patients with optic neuritis associated with acute transverse myelopathy in multiple sclerosis].

We reviewed the records of 20 patients with optic neuritis who were diagnosed to have clinically definite multiple sclerosis (MS). We classified them into 2 subgroups: group A, consisting of 9 patients who had acute transverse myelopathy (ATM); and group B, 11 patients without ATM. 4 patients (44%) in group A had complete visual loss, but none in group B. 6 patients (67%) in group A had less than 0.1 visual acuity in the affected eye, but only 2 patients (18%) in group B. 4 patients in group A had evidence of anticardiolipin antibodies. While both groups were diagnosed as having clinically definite MS, there were differences in the clinical features between them. We assume that the patients with ATM constitute a different subgroup among MS patients.

Acute Disease↗

[A case of ventricular septal defect and patent ductus arteriosus associated with absent right pulmonary artery, scimitar syndrome and severe pulmonary hypertension].

A 8 month-old female was diagnosed with ventricular septal defect and patent ductus arteriosus associated with absent right pulmonary artery and scimitar syndrome. Cardiac catheterization revealed severe pulmonary hypertension as follows; 72 mmHg of mean pulmonary artery pressure, 0.56 Qp/Qs and 1.73 Pp/Ps. Temporary closure of the ductus reduced the mean pulmonary artery pressure from 72 to 40 mmHg. PDA was ligated and VSD was closed successfully. However, 4 months after initial operation she was readmitted due to infection of the hypoplastic right lung. Removal of the hypoplastic right lung was performed and postoperative course was uneventful.

Ductus Arteriosus, Patent↗

[Myocardial protection and the sarcoplasmic reticulum--the effect of ryanodine treatment prior to cardioplegic arrest on post-ischemic functional recovery].

Sarcoplasmic reticular (SR) calcium depletion may contribute to the myocardial protection against ischemia and reperfusion-induced injury. We have, therefore, investigated the effect of ryanodine-induced SR calcium depletion on the myocardial protection when given during Langendorff perfusion before ischemia in the isolated working rat heart. Hearts (n = 6/group) from male Wistar rats were aerobically (37 degrees C) perfused (20 min) with bicarbonate buffer (the first working perfusion), and then aerobically (37 degrees C) perfused with bicarbonate buffer containing 0, 1.75 or 7.00 nmol/L of ryanodine (a Langendorff perfusion). Hearts were then aerobically (37 degrees C) perfused (20 min) with ryanodine-free bicarbonate buffer (the second working perfusion). This was followed by a 3 min infusion of St. Thomas' Hospital cardioplegic solution, and then subjected to 38 min of normothermic (37 degrees C) global ischemia and 35 min of reperfusion (15 min Langendorff, 20 min working). After the ryanodine treatment, the percent reduction in aortic flow was significantly greater in the 7.00 nmol/L ryanodine group than in the control group. The post-ischemic recoveries of aortic flow were 39.1 +/- 3.3, 32.8 +/- 5.3 and 37.3 +/- 4.4% in the 0, 1.75 and 7.00 nmol/L ryanodine groups, respectively. There was no difference in the creatine kinase leakage during Langendorff reperfusion between the ryanodine-treated groups and the control group. Thus, ryanodine decreased the cardiac function after the ryanodine treatment, indicating a reduction in SR calcium content. Ryanodine, however, failed to improve the post-ischemic functional recoveries.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

[Sarcoplasmic reticular calcium release and myocardial protection--effect of ryanodine on myocardial ischemia and reperfusion-induced injury].

Calcium release from sarcoplasmic reticulum (SR) may contribute to the intracellular calcium overload observed during myocardial ischemia and reperfusion. We have therefore investigated the ability of ryanodine to enhance myocardial protection when given before ischemia or during reperfusion in the isolated working rat heart. Hearts (n = 6-9/group) from male Wistar rats were aerobically (37 degrees C) perfused (20 min) with bicarbonate buffer (Ca2+ = 2.4 mM). In the first series of studies, this was followed by a 3 min infusion of St Thomas' Hospital cardioplegic solution containing various concentrations of ryanodine. Hearts were then subjected to 38 min of normothermic (37 degrees C) global ischemia and 35 min of reperfusion (15 min Langendorff, 20 min working). The recoveries of aortic flow (%AF) were 50.3 +/- 2.5% in the ryanodine free controls versus 55.2 +/- 5.8, 72.0 +/- 1.3 (p < 0.05), 61.0 +/- 4.3, 51.8 +/- 5.1 and 32.1 +/- 5.0 (p < 0.05)% in the 0.88, 1.75, 2.13, 2.50 and 10.00 nM ryanodine groups, respectively. Creatine kinase (CK) leakage during Langendorff reperfusion was reduced in the 1.75 nM group but was similar to control in all other groups. In the second series of studies, 3 min of cardioplegia without ryanodine and 38 min of ischemia (37 degrees C) were followed by 15 min of Langendorff reperfusion with 0, 0.09, 0.18, 0.88 or 1.75 nM ryanodine, %AF was 59.3 +/- 3.3%, 54.7 +/- 3.3, 53.8 +/- 3.5, 38.4 +/- 8.9 (p < 0.05) and 33.3 +/- 5.8 (p < 0.05)% in the 0, 0.09, 0.18, 0.88 and 1.75 nM ryanodine groups, respectively. CK leakage tended to increase dose-dependently.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Molecular characteristics in Japanese patients with lipidosis: novel mutations in metachromatic leukodystrophy and Gaucher disease.

The characterization of mutations in Japanese patients with lipidosis, particularly in metachromatic leukodystrophy (MLD) and Gaucher disease has been studied in detail. Metachromatic leukodystrophy is characterized by an accumulation of sulfatide in nervous tissues and kidney due to a deficiency of arylsulfatase A (ASA). We analyzed the presence of three known mutant arylsulfatase A alleles in Japanese patients with MLD. Among 10 patients of Japanese patients with MLD, we found that allele 445A mutation has moderately high incidence and also homozygosity of this mutation results in the late infantile form. Allele 2381T was not found in Japanese patients. Furthermore, we found novel mutation which is G- to A mutation at the 1070 nucleotide of the ASA gene (designated 1070 A) in Japanese patients with juvenile onset. This mutation results in a amino acid substitution of Gly245 by Arg and found in heterozygote form. Our studies of molecular analysis in 10 Japanese patients with MLD indicate that Japanese MLD patients have unique characteristics of ASA mutations compared with those of Caucasian patients. On the other hand, Gaucher disease is the most prevalent sphingolipidosis, characterized by an accumulation of glucocerebroside in macrophage derived cells due to a deficiency of lysosomal hydrolase glucocerebrosidase. To study the molecular basis of Gaucher disease in Japanese patients, we analyzed the presence of the two known mutations (6433C and 3548A) in the glucocerebrosidase gene of 15 patients with Gaucher disease. We found that the 6433C and 3548A mutations occur in all subtypes of Japanese patients with Gaucher disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Immunoelectron microscopic detection of estrogen target cells in the bone marrow of estrogen-treated male Japanese quail.

The localization of estrogen receptors (ERs) in bone marrow cells was studied immunoelectron microscopically in the femurs of estrogen-treated male Japanese quail. The electron-dense reaction product showing ER localization was not detected in the bone marrow cells of the male quail. After 48 h of estrogen treatment, nuclear reaction product was observed in many mononuclear cells in the bone marrow. Most were located in the marrow stroma, and they were divided into undifferentiated and differentiated type cells, characterized by poorly and well-developed cytoplasm, respectively. Some ER-positive cells were situated in the hematopoietic tissue and had moderately developed cytoplasm. Thus, estrogen target cells may be present in the stroma and hematopoietic tissue of bone marrow.

Animals↗

Study on zwitter-ionization of drugs. II. Synthesis and pharmacological activity of some N-[3-(5H-dibenzo[a, d]cyclohepten-5-ylidene) propyl]-N-methylamino- and N-[3-(6H-dibenz[b, e]oxepin-11-ylidene) propyl]-N-methylamino-alkanoic acid derivatives and related compounds.

A series of N-[3-(5H-dibenzo[a, d]cyclohepten-5-ylidene)propyl]-N-methylamino- (6a) and N-[3-(6H-dibenz-[b, e]oxepin-11-ylidene)propyl]-N-methylamino-alkanoic acid derivatives (6b) and related compounds (6c-f) were synthesized and examined for pharmacological activities in vitro, i.e., inhibitory effect on monoamine [noradrenaline (NA) and 5-hydroxytryptamine (5-HT)] uptake, inhibitory effect on 5-HT-, histamine-, acetylcholine- and NA-induced contraction, and binding affinity for alpha 2-adrenoceptor and dopamine D2-receptor. In vitro tests indicated that zwitter-ionization was capable of maintaining H1-antihistaminic activity while greatly reducing other pharmacological activities. Further, 6a-f showed much stronger inhibitory effects on compound 48/80-induced lethality in rats than did the corresponding N,N-dimethylamines (2a-f). 3-[N-[3-(6H-Dibenz[b, e]oxepin-11-ylidene)propyl]-N-methylamino]- propionic acid (6b-2), selected as a candidate antiallergic agent of a new type, equally potent in rats and guinea-pigs, exhibited strong inhibitory effects on 48 h homologous passive cutaneous anaphylaxis (PCA) in rats (ED50 = 0.019 mg/kg, p.o.) and on histamine-induced bronchoconstriction in anesthetized guinea-pigs (ED50 = 0.0067 mg/kg, p.o.).

Amitriptyline↗

Molecular cloning of feline interleukin-6 cDNA.

We cloned and sequenced feline interleukin-6 (IL-6) cDNA using the polymerase chain reaction (PCR) technique to obtain information on regulation of the IL-6 gene. The feline IL-6 cDNA cloned in this study was 752 bp long and included all the amino acid coding region. At the amino acid level, the overall identities of the feline IL-6 to the human and murine counterparts were 58% and 39%, respectively. After transfection with the expression vector containing the cDNA, CRFK cells produced biologically active proteins that showed hybridoma growth promoting activity.

Amino Acid Sequence↗

Type 1 (insulin-dependent) diabetic patient with remarkable infiltration of lymphocytes to the islets.

We report the case of a 62-year-old woman who was admitted to our hospital with diabetic ketoacidosis. Her urinary C-peptide was 3.5 micrograms/day, HLA typing was DR9, and serum was positive for islet cell antibodies. There was no significant increase in the major viral titer. Pancreatic head tumor was suspected, and pancreaticoduodenectomy was performed. The pathology of this tumor was polycystic adenoma. We examined the surgical specimen from around the tumor histologically. The pancreatic islets had decreased in number. The immunohistochemical staining of islets for insulin, glucagon and somatostatin showed that the number of B cells had decreased remarkably, while A and D cells were preserved. Marked lymphocytic infiltration was observed in the islets. The majority of lymphocytes were helper/inducer and suppressor/cytotoxic T cells, which did not express HLA-DR antigen or interleukin-2 receptor. No NK cells were present in the islets. The present case, which was examined histologically in detail, is consistent with the previously proposed hypothesis that autoimmunity might play an important role in the pathogenesis of insulin-dependent diabetes mellitus.

Adenoma↗

[A case of carbamazepine-induced lupus with myositis].

This is the report with muscle disorder associated carbamazepine (CBZ)-induced lupus. A 39-year-old female had been treated with CBZ 400 mg per day for 2 years because of complex partial seizure. In November, 1992 laboratory studies showed elevation of serum CK, IgG and titers of antinuclear antibody. Physical examination on admission revealed muscle weakness of neck flexors and iliopsoas but no rash or arthralgia. The electromyography showed myogenic change in the right biceps. CBZ was discontinued and replaced by zonisamide. Prednisolone 40 mg daily was started and the patient steadily improved. In the literature, there have been a few cases with muscle symptoms in CBZ-induced lupus, but muscle involvement with highly elevated CK associated with CBZ-induced lupus has not been reported.

Adult↗

[Molecular diagnosis and gene therapy for Gaucher disease].

Gaucher disease is the most prevalent lysosomal storage disease. It is caused by deficient activity of a lysosomal enzyme known as glucocerebrosidase, also called glucosylceramidase, resulting from mutations in the gene encoding the enzyme. The numerous mutations in glucocerebrosidase gene from patients were reported and the correlation of phenotype and genotype were studied. However, a given genotype cannot be uniquely correlated with a specific phenotype. In the therapeutic point of view, two successful treatment were developed based on the correction of the enzyme deficiency in macrophages. These are bone marrow transplantation and enzyme infusion therapy. Although patients have responded to these two therapies, inherent problems limit their application. Thus, these problems makes Gaucher disease an excellent candidate for therapy based on gene transfer to hematopoietic cells. We succeeded in efficient transduction and sustained high expression of glucocerebrosidase gene in mouse hematopoietic stem cells and macrophages from long term reconstituted mice. The results of our study strengthen the rationale for gene therapy as a treatment for Gaucher disease.

Animals↗

[Experimental study of acute spinal cord injury: a histopathological study].

The microscopic appearance of a rat spinal cord which was acutely compressed by aneurysmal clip for one minute, was investigated 15 minutes, 30 minutes, 1 hour, 3 hours and 6 hours after the injury. Although the resulting small hemorrhagic lesion involved primarily only the central gray matter of the injured portion 15 minutes after compression injury, hemorrhage, necrosis and edema in the central gray matter enlarged progressively until 3 hours after injury. Petechial hemorrhage, necrosis and edema were observed in the surrounding area one hour after spinal compression. Then these pathological changes extended rostrally and caudally, but their extension was more significantly remarkable in the rostral side than in the caudal side 3 hours after compression. It was observed that leukocytes begin to infiltrate into the injured capillary walls and plug up the capillary lumen 30 minutes after the injury. Three hours following the injury, leukocytes (lymphocyte, macrophage) extravasated into the surrounding spinal tissue. From these histopathological observations, we reached the following conclusions. A. Secondary injuries play an important role in grave impairment of neurological function of the spinal cord following acute trauma. B. Pathological findings (hemorrhage necrosis and edema) extend more prominently to the rostral side, because the direction of spinal blood flow may be rostral in the thoracic spinal cord. C. Severe disturbance of intraspinal capillary blood flow leading to grave spinal damage may be evoked, because leukocytes infiltrate into the capillary around the injured area and plug up the their lumen about 30 minutes after the injury.

Acute Disease↗

[Clinical application of recombinant human SOD for the protection of ischemia reperfusion injury during open heart surgery].

We have applied recombinant human superoxide dismutase (RH-SOD) to prevent ischemia reperfusion injury in the patients who received open heart surgery. Twenty-four patients were divided into 2 groups; group A had no treatment as control and group B received bolus injection of RH-SOD (35,000 IU/kg) into cardiopulmonary bypass 5 minutes before reperfusion. Arterial and coronary sinus blood was collected to measure chemiluminescence (ChL) value, SOD activity, lactate and pyruvate level, and several parameters of myocardial oxygen metabolism after reperfusion. Arterio-venous difference of ChL value showed the tendency of less ChL generation of the heart in group B compared with those in group A. But no other parameters showed significant difference between the two groups. Our data suggested that this way of the administration of RH-SOD failed to improve the myocardial protection during open heart surgery. Further investigation, such as dose response study, might be required to determine whether RH-SOD possess beneficial effects or not in the clinical setting.

Heart Arrest, Induced↗

[Experimental study of acute spinal cord injury: a study of spinal blood flow].

It is well known that the worsening of neurological findings after spinal cord injury is due to the secondary progression of pathological changes which may be caused by spinal cord blood flow disturbance. We measured spinal blood flow of 5mm rostrally and caudally distant portions from the injured point, using the laser Doppler flowmeter experimentally. Forty rats were used. Ten of these were used as a control group. And thirty animals were injured at the level of the tenth thoracic cord with a 50g epidural one minute compression method and measured continuously from 30 minutes before the injury to 6 hours after the injury. Twenty two surviving animals were evaluated. In the control group, spinal blood flow was stable. But in the injured group, spinal blood flow dropped by 30.6 + 9.8% on the rostral side and 37.3 + 17.6% on the caudal side in comparison with the resting value soon after the injury. Although the flow improved to 89.3 + 11.1 and 71.3 + 17.8% respectively 15 minutes later, it dropped again gradually and reached 42.8 + 14.1 and 66.2 + 16.4% respectively 6 hours after the injury had been inflicted. Lastly, in the animals, carbon perfusion was performed through the left ventricle. The normal figured vasculature in the preparation of the injured and measured portion was calculated with a microcomputer imaging analyzer and compared with control groups. The number of the normal vessels was significantly more abundant on the caudal side than on the rostral side (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

Efficient transfer and sustained high expression of the human glucocerebrosidase gene in mice and their functional macrophages following transplantation of bone marrow transduced by a retroviral vector.

A recombinant retroviral vector (MFG-GC) was used to study the efficiency of transduction of the human gene encoding glucocerebrosidase (GC; D-glucosyl-N-acylsphingosine glucohydrolase, EC 3.2.1.45), in mouse hematopoietic stem cells and expression in their progeny. Transfer of the GC gene to CFU-S (spleen cell colony-forming units) in primary and secondary recipients was virtually 100%. In mice 4-7 months after transplantation, highly efficient transfer of the human gene to bone marrow cells capable of long-term reconstitution was confirmed by detection of one or two copies per mouse genome in hematopoietic tissues and in cultures of pure macrophages. Expression of the human gene exceeded endogenous activity by several fold in primary and secondary CFU-S, tissues from long-term reconstituted mice, and explanted macrophages cultures. These studies are evidence of the feasibility of efficient transfer of the GC gene to hematopoietic stem cells and expression in their progeny for many months after reconstitution. The results of this study strengthen the rationale for gene therapy as a treatment for Gaucher disease.

Animals↗