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Biomedical subjects

T Yasuda

Publications and source records attributed to T Yasuda.

At least 703 records · Page 39Linked to original sources

Rat parathyroid hormone-like peptide: comparison with the human homologue and expression in malignant and normal tissue.

A rat Leydig cell tumor cDNA library was screened with a 32P-labeled genomic restriction fragment encoding human PTH-like peptide (hPLP), and three cDNA clones were isolated. The largest cDNA insert contained 1146 nucleotides. The cloned cDNA encodes a 177-amino acid protein consisting of a predicted 36-amino acid leader sequence and a 141-amino acid mature peptide in which 9 of 13 amino-terminal residues are identical to rat PTH (rPTH). Comparison of rPLP with hPLP reveals marked conservation of both the nucleotide and amino acid sequences through the prepro, amino-terminal, and midregion portions of the molecules. There is also striking conservation of the 3' noncoding regions of rPLP and hPLP mRNAs, both of which contain AU-rich repeated sequences that may affect mRNA stability. A single species of mRNA of approximately 1.4-kilobases was identified in the rat Leydig cell tumor and in normal rat stomach. Southern blot analysis is consistent with the presence of a single copy of the rPLP gene per haploid genome, and there is no major rearrangement or amplification of the rPLP gene in DNA isolated from the tumor per se. The results demonstrate the presence of a single gene transcript in a rat model of malignancy associated with hypercalcemia which encodes a peptide homologous to hPLP, document the marked interspecies sequence conservation that exists in major functional domains of the mRNAs and peptides, and show the expression of mRNA encoding rPLP in normal stomach as well as in neoplastic rat tissue.

Amino Acid Sequence↗

Nerve growth factor receptor immunoreactivity in the neuronal perikarya of human sensory and sympathetic nerve ganglia.

We examined immunohistochemically the dorsal root ganglia, sympathetic ganglia, spinal cord, ventral and dorsal roots, and sciatic nerves obtained at autopsy from adult humans, using a monoclonal antibody against the human nerve growth factor receptor. We observed labelling in a granular pattern in the neuronal perikarya of dorsal root and sympathetic nerve ganglia. Ventral horn cells and axons were not labelled.

Antibodies, Monoclonal↗

Enzyme immunoassay for oxytocin.

A competitive, double antibody enzyme immunoassay for oxytocin in a heterologous system was developed. Horseradish peroxidase was conjugated with oxytocin using N-succinimidyl 3-(2-pyridyldithio) propionate, and rabbit anti-oxytocin serum was produced by immunization of oxytocin-bovine serum albumin complex which was prepared by the carbodiimide method. The sensitivity of the assay was 4 microIU/tube, which corresponded to 10 microIU per ml using 400 microliters of the sample which was extracted from the same volume of plasma by means of SEP-PAK C18 cartridges. The coefficients of variation for different levels of oxytocin ranged from 6.8-15.9% and 8.5-16.7%, for intra- and inter-assay. Recovery of oxytocin added to plasma after extraction was 99-117%. No or little cross-reaction with arginine- and lysine-vasopressin was found. Plasma oxytocin concentrations determined by the proposed enzyme immunoassay were well correlated with those determined by radioimmunoassay (r = 0.90).

Immunoenzyme Techniques↗

Erythropoietic activity in culture media conditioned by rat mesangial cells.

Using a tissue culture technique we examined erythropoietin (EPO) producing cells in rat glomeruli. In 5 out of 6 independent glomerular cell cultures, EPO activity was found in the mesangial-cell proliferating phase, but not in the epithelial-cell proliferating phase. Therefore, mesangial cells seemed to be EPO producing cells.

Animals↗

Structure activity relationships in PIPC-analogues against Pseudomonas aeruginosa.

The relationship between the chemical structure and mode of action of piperacillin-analogues (PIPC-analogues) against Pseudomonas aeruginosa was investigated. The antibacterial activities of PIPC-analogues became stronger as the chain length of the alkyl group on the N-4 position in 2,3-dioxopiperazine when tested in constitutively beta-lactamase-producing strain, but not paralleled in wild and beta-lactamase-less strains. The outer membrane permeability was hardly affected by the chain length of the alkyl group at the N-4 position. The stability to beta-lactamase was stronger with the increase of the number of the carbon atoms of N-4 position. In the binding-affinities to the lethal penicillin-binding proteins (PBPs), compounds PIPC (C-2), C-3 and C-4 showed lower ID50 values than compounds C-1, C-6 and C-8. These results suggested that the stability to beta-lactamase was the governing part for the antibacterial activity in constitutively beta-lactamase-producing strain, and the binding affinity to lethal PBPs directly contributed to the antibacterial activity in wild and beta-lactamase-less strains.

Bacterial Outer Membrane Proteins↗

[Importance of the conjugated antibody for the induction of selective effect of adriamycin conjugated with anti AFP monoclonal antibody and entrapped in liposomes against AFP producing tumors].

We investigated experimentally the effect of adriamycin (ADM) conjugated with anti alpha-fetoprotein (AFP) monoclonal antibodies and entrapped in liposomes (Lip-ADM = AbAFP) in vitro or in vivo. In the present study, we examined the importance of the conjugated antibody for the induction of selective therapeutic effect of Lip-ADM = AbAFP against AFP producing tumors. As the target tumors, AFP producing human hepatoma strain, Li-7, and AFP non-producing human breast cancer strain, MX-1 maintained in BALB/c nu/nu male mice were used. In order to evaluate the importance of the conjugated antibody, we prepared also ADM conjugated with normal mouse IgG, and entrapped in liposomes Lip-ADM = NIgG, of which therapeutic effects were compared with that of Lip-ADM = AbAFP. Judging from the tumor growth curve and the tumor weight, the therapeutic effect of Lip-ADM = AbAFP was greater against Li-7 than that of Lip-ADM = NIgG. On the other hand, both conjugates showed similar effects against MX-1. As the results it is suggested that the antibody which recognizes the antigen expressed on the target tumor cells can solely increase the therapeutic effect of ADM entrapped in liposomes (Lip-ADM) and that the main factors which contribute to the efficient therapeutic effect of the conjugate were the sensitibility to ADM, the affinity of the tumor cells to liposomes and the superiority of the conjugated antibody.

Animals↗

[Preventive effects of intra-arterial infusion chemotherapy of liver metastasis in non-resectable pancreatic cancer].

This is a study which evaluates intra-arterial chemotherapy for non-resectable carcinoma of the pancreas without liver metastasis (locally advanced). Twenty-one patients received ia-chemotherapy (MA-CP: Methotrexate + Angiotensin II----Citrovorum factor + Prostaglandin E1). They showed a 39% 1-year survival rate and 92% of 1-year cumulative rate of survival without liver metastasis. These incidences were significantly higher than those of (13%, 50%) 52 patients who underwent systemic chemotherapy (control). As the reason for such significant differences, we suspected that a high dose of chemotherapeutic view after MTX had been infused into the pancreatic-supplying arteries. This speculation was confirmed by the serial determination of the MTX concentration in the portal blood.

Alprostadil↗

[Hypoglycemia induced by insulin antibody during postoperative management with intravenous hyperalimentation--a case report and qualitative analysis of insulin antibody].

A 42-year-old male began to show frequent hypoglycemic attacks, 25 days after total gastrectomy. By that time, he had received intravenous hyperalimentation therapy with bovine insulin. Incidence of these attacks increased despite the dose of glucose was escalated and insulin administration was interrupted. Serum C-peptide level was 11.4 ng/ml and total immunoreactive insulin (IRI) level was 1170 mu u/ml with 1120 mu u/ml (96%) of gamma-globulin-binding IRI. Since insulin antibody formation was suspected, we decreased the dose of glucose to reduce the endogenous insulin production. Consequently total IRI, binding IRI and C-peptide levels decreased, and hypoglycemic attacks disappeared. These results imply that insulin antibody, once induced by bovine insulin, binds with endogenous insulin. Therefore, it is concluded that heterogenous insulin should not be given during hyperalimentation, especially for patients with good glucose tolerance. When insulin antibody developed, it is effective to reduce the dose of glucose in order to decrease endogenous insulin production.

Adult↗

[Boron neutron capture therapy using 10B entrapped anti-CEA immunoliposome].

A new murine monoclonal antibody (2C-8) was prepared by immunizing mice ip with CEA producing human pancreatic cancer cell line, AsPC-1.SDS-PAGE and Western blot analysis showed that 2C-8 monoclonal antibody recognized CEA and NCA. This anti-CEA monoclonal antibody was conjugated with large multilamellar liposomes incorporated 10B compound (Cs2 10B12H11SH). This immunoliposomes applicated to boron neutron capture therapy. AsPC-1 cells were incubated with the 10B-Lip-MoAb(CEA) for 8 hours. After the irradiation with thermal neutron (1 x 10(11)-1 x 10(13) n/cm2), boronated AsPC-1 cells were showed decreasing uptake of 3H-TdR compared with control group. The numbers of 10B atoms in liposomes bound to an antibody were in proportion to the dose of 10B compounds added and maximum number of 10B atoms was approximatory 1.2 x 10(4)/Ab. These data indicated that the immunoliposomes could deliver highly amount of 10B atoms to the tumor cells and exert cytotoxic effect by thermal neutron. BNCT with immunoliposome may be useful to the non resectable malignant tumors in clinical application.

Animals↗

[Evaluation of long survival cases treated with intra-arterial cancer chemotherapy using implantable reservoirs].

We have treated unresectable liver tumor with intraarterial infusion chemotherapy using an implantable reservoir since 1983. Out of the total 44 cases receiving the chemotherapy during the period from 1983 to February 1989, the evaluation of 8 cases (18.2%) surviving over a year is reported. The 8 cases consist of 3 cases of primary hepatic cancer, 4 cases of metastatic hepatic cancer and 1 case of malignant hemangiopericytoma of pelvis. The cases of primary hepatic cancer are 2 cases of hepatoma (413, 420 days) and 1 case of cancer of bile-duct (400 days). The metastatic cases are 1 case of gastric cancer (826 days), 2 cases of colo-rectal cancer (698, 1080 days) and 1 cases of leiomyosarcoma of small intestine (577 days). A case of malignant hemangiopericytoma of pelvis has survived 4 years and 3 months after the infusion chemotherapy via the internal iliac artery. The two cases of colo-rectal cancer were treated with continuous infusion of FUDR via the proper hepatic artery using Infusaid. For the other cases, ADM and CDDP were infused repeatedly with single-shot type Infuse-a port. Intra-arterial infusion chemotherapy is very useful because treatment in the outpatient clinics is possible over the longterm, and it is possible for patients receiving the therapy to maintain quality of life.

Adult↗

[Expression of nerve growth factor receptor in human benign peripheral nerve sheath tumor].

We examined in vivo and in vitro expression of nerve growth factor (NGF) receptors in 13 dermal and 9 plexiform neurofibromas, 28 schwannomas, and 4 traumatic neuromas with an immunohistochemical method using a monoclonal antihuman NGF receptor antibody (ME20-4) and anti S-100 beta protein antibody. Immunoreactivity for NGF receptor and S-100 beta protein was universally observed on the principal cells of both neurofibroma and schwannoma in vivo. Moreover, we examined the NGF receptor and S-100 beta protein immunoreactivity in the culture system of the neurofibroma and schwannoma with an immunofluorescent double staining method. The principal cells of both tumors were positively stained by both ME20-4 and anti S-100 beta protein antibodies. These cells also express the ability for 125I-NGF binding, which was examined with an autoradiographic technique. These results suggest that NGF receptors are universally expressed on the S-100 beta protein positive Schwann-like cells composing of these tumors both in vivo and in vitro. In traumatic neuroma, however, a positive staining of NGF receptor was more strongly observed in the perineurium rather than in the endoneurial cells.

Adolescent↗

[Antineuronal antibody in carcinomatous neuropathy].

A seventy-year-old woman was admitted to the hospital because of paresthesias and progressive weakness of the extremities. Ten months previously, tightness in the thighs and numbness in the fingers developed, with subsequent tingling sensations of the hands and feet. Three months before entry, she had difficulty in walking because of severe paresthesias in the extremities. She was found to have an abnormal mass in a X-ray film of the chest, and transferred to our hospital. Neurological examination showed generalized hyporeflexia, marked loss of deep and discriminative sensations in the distal portion of the limbs, positive Romberg sign and severely ataxic gait. Cerebellar sign was negative. Cytologic examination of a transbronchial lung biopsy disclosed small cell carcinoma of the lung. A sural nerve biopsy showed severe loss of myelinated fibers accompanied by axonal degeneration of residual fibers. Immunohistochemically antineuronal antibody was found in the serum but not in the CSF, which reacted to nuclei and cytoplasm of the dorsal root ganglion neurons as well as Purkinje cells. Titers of this autoantibody in the serum were markedly reduced after chemotherapy and irradiation. Western blot analysis demonstrated that autoantibody in the serum recognized neuronal antigen with single band at 38 kd. Pathogenesis of carcinomatous neuropathy is still unexplained, but the findings here presented have given rise to the speculation that antineuronal antibody may be a contributory factor in carcinomatous neuropathy.

Aged↗

[Chronic recurrent-progressive polyradiculoneuritis--Characteristics of autonomic dysfunction].

We examined autonomic dysfunctions in 12 patients with chronic-recurrent-progressive polyradiculoneuritis (C-R-P-PRN), consisting of 6 males and 6 females with the clinical duration of 8 months to 16 years, and with the age ranged 13 and 71 years. Sixteen healthy volunteers, aged 20 to 70 years, were also examined. Thermal sweat rate was recorded on the palm, forearm, upper arm, anterior chest, lateral thigh and lateral aspect of lower leg using a ventilated capsular method in a climatic chamber at 40 degrees C and 40% of relative humidity. After steady state was attained, thermal sweat rate was measured. Local sweating induced by intradermal injection of pilocarpine and nicotine (a concentration of 10(-4), 0.1 ml) was also measured on the forearm and lower lateral leg at 23 degrees C of room temperature and 40% of relative humidity. Other autonomic functions including skin temperature at rest and after cold loading (15 degrees C, 6 minutes), variation in the R-R interval (CV%), pupillary function (response to 1.25% epinephrine, 2(-5) pilocarpine, 5% tyramine), orthostatic hypotension and bladder dysfunction were also monitored. A decrease in sweat rate and recovery rate of skin temperature was seen more frequently in patients with C-R-P-PRN than normal volunteers. Abnormality in the thermal sweat rate and local sweat response against nicotine and pilocarpine was present more frequently in the forearm and distal leg as compared with the chest and thigh.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[Bilateral abductor vocal cord paralysis (Gerhardt syndrome) in the Shy-Drager syndrome].

Ten consecutive patients with a progressive pan-autonomic failure of the Shy-Drager syndrome were investigated. Movement disorders of the vocal cords were examined with a fiber-optic laryngoscope as well as a video-recorder. Moderate to severe vocal cord paralysis was present in five of ten patients. The vocal cords were almost immobile during inspiration, while there was no limitation of the adduction during phonation. In two cases, grade of vocal cord paralysis was asymmetric. One patient developed peculiar twisting-like dystonic movements of the vocal cord. Polygraphic studies revealed that SaO2 was lowered in spite of tachypnea during sleep. In two cases, the expiratory flow volume curve in effort-dependent portion near TLC showed a plateau and the inspiratory part of the curve also showed a plateau indicating constant flow. These functional disorders suggest an upper airway obstruction probably due to the vocal cord dysfunction. There was no vocal cord paralysis in two patients who had neither snore nor stridor. Development of a severe vocal cord dysfunction usually manifested itself clinically as stridor, snore or respiratory failure requiring tracheostomy. There was little information on the pathology of the vagal nerves and nuclei supplying motor control to the laryngeal muscles. The mechanism of the selective involvement of abductor muscle (posterior muscle) of the vocal cord (Gerhardt syndrome) remains unsolved. Vocal cord paralysis should be looked for since it can result in respiratory failure leading to death.

Adult↗

[Single photon emission computed tomography (SPECT) using 99mTc-hexamethyl propyleneamine oxime in patients with ischemic cerebral diseases: comparative study of N-isopropyl-p-[123I]-iodoamphetamine and 99mTc-DTPA SPECT].

In order to confirm the diagnosis and clarify the pathophysiology in the ischemic lesions in brain, 99mTc-PAO SPECT was performed in 42 patients with ischemic cerebral diseases, and the findings on 99mTc-PAO SPECT were compared with those on 123I-IMP or 99mTc-DTPA SPECT, and on X-CT. Furthermore, count ratio of ischemic lesion to normal contralateral region (I/N) was used for the evaluation of the detectability in the lesions on 99mTc-PAO or 123I-IMP SPECT, and less than 0.95 of I/N ratio was defined as the decreased accumulation. The detectability of ischemic lesion in brain with 99mTc-PAO SPECT was 80%, which was superior to that (60%) of LDA on X-CT. Especially, 99mTc-PAO SPECT was useful in cases which were examined early after the onset of the attack. On the other hand, 123I-IMP SPECT showed the best result (88%) in the detectability, and furthermore I/N ratio on 123I-IMP SPECT was lower than that on 99mTc-PAO SPECT. In the delayed phase on 123I-IMP SPECT the redistribution was observed in 30%, while on 99mTc-PAO SPECT it was done in none of them. The accumulation of 99mTc-DTPA in brain was found in 6 of 14 cases (43%), and 2 cases among them also showed the accumulation of 99mTc-PAO in the ischemic lesion. In such cases the destruction of BBB might be considered as the cause of the accumulation of 99mTc-PAO. Thus, 99mTc-PAO SPECT was thought to be useful method in clinical studies of the ischemic cerebral diseases.

Amphetamines↗