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Biomedical subjects

S Maeda

Publications and source records attributed to S Maeda.

At least 829 records · Page 46Linked to original sources

Cloning, expression and location of the Streptococcus lactis gene for phospho-beta-D-galactosidase.

Genes for lactose catabolism and proteinase production in Streptococcus lactis 712 are encoded by a 56.5 kb metabolic plasmid, pLP712. A lactose mini-plasmid of only 23.7 kb, pMG820, was constructed by introducing two deletions into pLP712, and was cloned as two segments of DNA into the Escherichia coli vector pAT153 using restriction endonuclease PstI. The lactose genetic region of pLP712, which has been defined by deletion and restriction mapping, was cut into two parts by this process. When the smaller 10.8 kb segment of pMG820 DNA was present, the key lactic streptococcal lactose splitting enzyme, phospho-beta-D-galactosidase, was expressed in E. coli. The gene for phospho-beta-D-galactosidase was more precisely located by introducing a series of deletions into cloned DNA by in vitro manipulations and then assaying for enzyme activity. The presence of this phospho-beta-D-galactosidase activity was correlated with the production of a 58 kDa 35S-labelled protein both by E. coli minicells and after coupled transcription and translation of cloned DNA. The product of a second gene, a 37 kDa protein ('protein X'), and a possible truncated phospho-beta-D-galactosidase protein of 16 kDa were also detected in minicells.

Cloning, Molecular↗

Two cases of adult T-cell leukaemia.

A 70-year-old male and a 46-year-old female, both living in Japan, were seen because of multiple erythematous papules and plaques on the trunk and extremities. The peripheral white blood cell counts were increased to 30,000-80,000/mm3. The majority of white cells had characteristic lobulated and deeply indented nuclei. The patients and most of their family members had anti-ATLV antibody. Using an OKT series of monoclonal antibodies the tumour cells were found to be T-cells. Trisomy 21 was detected in the first case and ATL virus proviral DNA in the second.

Aged↗

Familial amyloidotic polyneuropathy diagnosed by cloned human prealbumin cDNA.

A diagnosis of familial amyloidotic polyneuropathy (FAP) can be made by use of restriction endonuclease NsiI, a cloned human prealbumin cDNA and Southern blot procedures. Digests of DNAs from 10 disease-free individuals showed two bands (6.6 kb and 3.2 kb) complementary to a human prealbumin cDNA, whereas digests from 11 individuals with FAP exhibited two additional bands (5.1 kb and 1.5 kb). We interpret these changes in pattern to be the result of a restriction site for NsiI located in the altered codon and associated with the mutant prealbumin gene. All these individuals with FAP were heterozygous for the prealbumin gene, carrying one normal and one mutant gene.

Adult↗

Participation of opiate and serotonergic systems in brain conditioning stimulatory inhibition of the potentials evoked by tooth pulp stimulation in the pars caudalis of the trigeminal sensory nucleus of the rat.

Effects of conditioning stimulations of the nucleus raphe magnus (NRM), nucleus reticularis paragigantocellularis (NRPG), mesencephalic periaqueductal central gray (PAG), nucleus dorsomedialis hypothalami (DMH), corpus striatum (CP), sensory cortex (SCT) and visual cortex (VCT) and actions of morphine, naloxone and metergoline on the potentials recorded from the pars caudalis of the trigeminal sensory nucleus evoked by the electrical stimulation of rat incisor pulps were examined. The spinal potentials evoked by electrical stimulation of the pulp consisted of 3 components. Component 2 was mainly inhibited by morphine and antagonized by naloxone. Conditioning stimulation of NRM, NRPG, PAG, CP, SCT and DMH strongly inhibited component 2. VCT did not show any inhibition. 33-67% of antagonism was observed by naloxone in the NRM, NRPG, PAG, CP, SCT and DMH. On the other hand, 27-44% of antagonism was observed by metergoline, and the antagonism was not enhanced by the additional administration of naloxone. These results conclusively show that the endorphin system as well as the serotonergic system is in the series involved in the descending inhibition for nociception in the trigeminal sensory nucleus.

Animals↗

[The study of a two-dimensional polar representation of the cardiac SPECT image--a new method of displaying left ventricular wall motion].

A new method was developed to display left ventricular wall motion using two dimensional polar representation of cardiac SPECT image. After intravenous administration of 740 MBq (20 mCi) 99mTc (in vivo labeling of red blood cell), ECG-gated SPECT image of cardiac pool was recorded (32 directions, 180 degrees). The short axis images of left ventricle were constructed at end-diastole (ED) and end-systole (ES). Then the functional images of (ED-ES)/ED were calculated at each compatible slices and displayed in color according the degree of wall motion. In 8 cases with cardiac diseases this method was applied and clinically useful functional images could be obtained. The area of akinesia or hypokinesia are successfully demonstrated clearly separated from the area of normokinesia. We conclude that this method is useful to show left ventricular wall motion and to evaluate the segment and grade of abnormal wall motion of left ventricle.

Adult↗

Distribution of enkephalin-like immunoreactivity in the feline heart; its interrelation with substance P- and vasoactive intestinal polypeptide-like immunoreactive nerve fibers.

Distribution of enkephalin (Enk)-like immunoreactivity in the feline heart was investigated by indirect immunofluorescence method. Enk-like immunoreactive (Enk-IR) nerve fibers and cells predominated in the atria but were rare in the ventricles. Enk-IR cells were mainly distributed near sinoatrial (SA) node and between aorta and pulmonary artery. These cells were usually grouped in clusters near blood vessels or cardiac ganglia. Some Enk-IR cells appeared to extend their processes to other Enk-IR cells, cardiac ganglia, blood vessels and rarely cardiac muscles in the atria. Furthermore, substance P (SP)- and vasoactive intestinal polypeptide (VIP)-IR nerve fibers were closely associated with some Enk-IR cells. Moreover, the distribution and morphological profiles of Enk-IR cells were very similar to those of catecholamine (CA)-containing cells.

Animals↗

Structure and expression of the mutant prealbumin gene associated with familial amyloidotic polyneuropathy.

We have cloned a chromosomal DNA segment that covers the entire sequence for the mutant prealbumin gene associated with familial amyloidotic polyneuropathy, and determined the sequence of the gene including 581 base-pairs of the 5'-flanking region and 95 base-pairs of the 3'-flanking region, except for the internal portions of the second and third introns. This sequence was aligned with that of the previously determined normal prealbumin gene and both sequences matched perfectly except for a single-base substitution present in the second exon. This substitution is responsible for the transition from valine (GTG) to methionine (ATG) in the mutant prealbumin and creates NsiI and BalI restriction sites in the mutant prealbumin gene. We also analysed prealbumin mRNAs in the livers of a disease-free individual and one with familial amyloidotic polyneuropathy and confirmed that there is no difference in the levels and sizes of the prealbumin mRNAs between the two. As we have demonstrated already that individuals with familial amyloidotic polyneuropathy are heterozygous for the prealbumin gene, carrying one normal and one mutant gene, levels of the two different mRNAs within the liver of an individual with familial amyloidotic polyneuropathy were separately estimated and were demonstrated to be approximately equal.

Amyloidosis↗

The killing effect of subclasses of mouse IgG antibodies on schistosomula of Schistosoma japonicum.

The killing effect of IgG antibodies in sera from S. japonicum infected mice on schistosomula of S. japonicum was studied in vitro in the presence of complement. Immune mouse sera were fractionated over Protein A-Sepharose and IgG1, IgG2a, IgG2b and IgG3 were purified by affinity chromatography. The killing activity of each subclass of IgG antibodies against schistosomula was observed only in the presence of complement. The activity of IgG1 was higher than that of the other subclasses of IgG. In combination of the two or three subclasses of IgG, the additive mortality rate was given in all combinations of each subclass of IgG. These results support the view that the combination of various subclasses of IgG antibodies potentiates the resultant lethal effect on schistosomula.

Animals↗

[A case of colon cancer associated with schistosomiasis japonica].

A case of colon cancer associated with schistosomiasis japonica is reported. A 60-year-old man was admitted with the complaint of melena. Barium enema study revealed a colon tumor (type 1') 11 cm from the anal ring. Sigmoidectomy was performed, and no lymph node metastasis was observed. Histologically, the tumor was diagnosed as well-differentiated adenocarcinoma, and also many schistosoma ova were found not only in the lesion of the carcinoma, but also in the tissue surrounding the carcinoma. In the latter lesion, ova were observed beneath muscularis mucosae. The distributions of the ova in the anal side of the tumor were more dominant than those in oral side. We review the direct correlation between gastrointestinal tract cancer and the schistosomiasis japonica in other reports.

Adenocarcinoma↗

Enhanced inhibition of colony formation of human renal cell carcinoma in soft agar by the combination of alpha-difluoromethylornithine and recombinant gamma-interferon.

We studied the inhibitory activity of alpha-difluoromethylornithine (DFMO) and alpha-, recombinant beta-, and recombinant-gamma-interferons (alpha-, rec-beta-, and rec-gamma-IFNs) on in vitro growth of 3 established human urogenital tumors (KO-RCC-1 from renal cell carcinoma, Bewo from choriocarcinoma of the uterus, and HT-1197 from transitional cell carcinoma of the urinary bladder) and 16 primary renal cell carcinomas obtained by nephrectomy. Treatment with DFMO together with rec-IFN-gamma synergistically inhibited KO-RCC-1 cell growth in monolayer culture and in soft agar. The other two established cell lines were less susceptible to this treatment. Combination of DFMO and rec-IFN-gamma was more inhibitory than that of DFMO and either IFN-alpha or rec-IFN-beta. The polyamine content in KO-RCC-1 cells was decreased to a greater extent by combined treatment with DFMO and rec-IFN-gamma than that in Bewo and HT-1197 cells. The effect of these agents in 11 of the 16 primary renal cell carcinomas, which could show clonal growth in double layer soft agar, was examined. More than 50% inhibition of colony growth was seen in only one case (9%) treated with 5 mM DFMO alone and in 2 cases (18%) treated with rec-IFN-gamma alone (1,000 units/ml) but in 10 of the 11 cases (91%) with the combined treatment. Our results indicate that combined treatment with DFMO and rec-IFN-gamma can be more effective than that with either agent individually in inhibiting cell growth of human renal cell carcinoma in vitro.

Antineoplastic Combined Chemotherapy Protocols↗

Cell surface asparagine-linked sugar chains of human early myeloblastic leukemic cells (KG-1a).

The asparagine-linked sugar chains obtained from total cell surface membrane glycoproteins of human early myeloblastic leukemic cells (KG-1a cells) were studied. The sugar chains liberated by hydrazinolysis were purified by paper electrophoresis, paper chromatography, and Bio-Gel P-4 chromatography followed by analysis of exoglycosidase digestion and methylation study. Neutral oligosaccharides were all composed of high mannose type sugar chains. Acidic oligosaccharides were chiefly composed of typical bi-, tri-, and tetraantennary complex type sugar chains with Gal beta 1----4GlcNAc beta 1----groups and Neu-Ac alpha 2----3 or 6Gal beta 1----4GlcNAc beta 1----groups (in which Gal is galactosyl, GlcNac is N-acetylglucosamine, and NeuAc is N-acetylneuraminic acid) as side chains. Moreover the following two structures were identified in (in which Fuc is fucosyl): monosialyl bi- and triantennary sugar chains with a Gal beta 1----4(Fuc alpha 1----3)GlcNAc beta 1----group (X determinant) as one of the side chains; and monosialyl tetraantennary sugar chains with a Gal beta 1----4GlcNAc beta 1----3Gal beta 1----4GlcNAc group (repeating N-acetyllactosamine unit) as one of the side chains. These data together with our previous studies on sugar chains of K562 cells [early erythroblast], adult erythrocytes [H. Yoshima, N. Shiraishi, A. Matsumoto, S. Maeda, T. Sugiyama, and A. Kobata, J. Biochem. (Tokyo), 91: 233-246, 1982], and HL-60 cells [promyelocyte] [A. Mizoguchi, S. Takasaki, S. Maeda, and A. Kobata, J. Biol. Chem., 259: 11943-11957, 1984] strongly suggest that the cell surface asparagine-linked sugar chains alter in an orderly fashion, systematically in association with lineage and maturation stages during hematopoietic cell differentiation.

Asparagine↗

Monocytoid leukemia cell line CTV-1: morphological, immunological and isoenzymatic characteristics.

The human leukemia cell line CTV-1 was established from a case of acute monoblastic leukemia (AMoL). We analyzed the phenotypic marker profile of the CTV-1 cells in their original, untreated state and during induction of differentiation with the phorbolester 12-0-tetradecanoylphorbol 13-acetate (TPA). TPA led to morphological changes with signs of differentiation. Cell proliferation decreased in a dose-dependent fashion during exposure to TPA. In the surface marker analysis using a panel of 45 monoclonal antibodies (MoAbs) and several polyclonal antisera, CTV-1 cells were negative for markers of the T- and B-cell lineages, and were positive for several, but not all, myelomonocytic markers. Although the cells were reactive with the MoAb Leu-7 which identifies natural killer (NK) T-cells, no NK activity was detected. In the isoenzyme analysis of the four enzymes carboxylic esterase, acid phosphatase, hexosaminidase and lactate dehydrogenase (LDH) performed by isoelectric focusing on polyacrylamide gels, CTV-1 cells displayed isoenzyme profiles of immature myeloid cells. The overall marker profile of CTV-1 cells demonstrated cells of monocytoid origin arrested at a very early stage of differentiation, possibly close to the stage of precursor cells. As compared to other myelomonocytic cell lines, CTV-1 cells showed unusual morphological, immunological, functional and biochemical features and appeared to be relatively insensitive to treatment with TPA, although some alterations of the phenotype could be induced.

Acid Phosphatase↗

[Management of left and right type intrahepatic stone associated with proximal bile duct stenosis].

Fifty-seven cases of intrahepatic stone were treated in our department from 1976 to 1984. Fifteen cases out of them were left and right type intrahepatic stone associated with the proximal bile duct stenosis. Treatments and results of these 15 cases are discussed. Percutaneous Transhepatic Cholangioscopy (PTCS) was performed in 10 cases, post operative cholangioscopy (POC) in 7 cases. These cases were divided into three groups according to the treatment received. Six patients were treated only with cholangioscopic lithotomy (Group I). Six patients underwent surgical treatment after cholangioscopic lithotomy (Group II). Other 3 patients were treated with POC (Group III). Clinical course of Group I: One patient died of recurrent liver abscess 5 years after PTCS. One died of another disease. One had suffered from empyema 5 years after PTCS, but he is doing well now. Other 3 patients are doing well now. Clinical course of Group II: All patients are doing well now. Clinical course of Group III: All patients underwent treatments for residual stones after POC. Good results were obtained in group II. Surgical treatment after cholangioscopic lithotomy is the best way for these 15 cases. Adequate operative procedure should be applied after improving the patients' condition and making an accurate diagnosis of biliary tract anomalies by means of PTCS.

Adolescent↗