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Biomedical subjects

M Fukuda

Publications and source records attributed to M Fukuda.

At least 1,009 records · Page 56Linked to original sources

Control of cisplatin-induced delayed emesis with metoclopramide and dexamethasone: a randomized controlled trial.

Forty-two patients with advanced lung cancer undergoing chemotherapy containing cisplatin (80 mg/m2) were submitted to a randomized controlled trial to evaluate the effect of the combination of metoclopramide and dexamethasone for the treatment of delayed cisplatin-induced emesis occurring more than 24 hours after cisplatin administration. All patients received intravenously (i.v.) high-dose metoclopramide and dexamethasone on the day of cisplatin treatment. Excellent emetic control (no emesis during the 24 hours following cisplatin administration) was achieved in 30 out of 41 patients (73%) with this combination. Patients treated i.v. with metoclopramide and dexamethasone on days 2-7 experienced less delayed emesis, nausea and anorexia compared to those treated with a placebo (delayed emesis, 25 vs 50%, respectively, P = 0.105; more than four days of nausea, 10 vs 35%, respectively, P = 0.059; less than three days of anorexia, 80 vs 50%, respectively, P = 0.048). Although the results of the study showed no statistically significant advantage with the combination of i.v. metoclopramide and dexamethasone for patients treated with cisplatin, in view of the short duration of anorexia and the marginal reduction in nausea. Female patients tended to have more emetic episodes and extrapyramidal side effects (except akathisia) than male patients, but the differences were not statistically significant except for acute emesis (P less than 0.005).

Adult↗

Computer-assisted retention prediction system for oligonucleotides in gradient anion-exchange chromatography.

A technique is presented for the retention prediction of single-stranded homo-oligonucleotides under gradient elution conditions in anion-exchange chromatography. The prediction system is based on the theory proposed by Jandera and Churacek. In the present system, the theory was modified by the extrapolation method, utilizing the linear relationship between the log of the capacity factor and the number of nucleotides. The modified theory allowed the prediction of retention times for high-molecular-weight oligonucleotides, which could not be calculated from the original theory. Oligoadenylate was used as a standard oligonucleotide to demonstrate the accuracy of the prediction system. By use of this system, the retention times of oligoadenylates up to 25-35 bases in chain length were predicted within 8% errors under both binary-linear and binary-convex gradient shapes.

Chromatography, High Pressure Liquid↗

Isolation and characterization of human lysosomal membrane glycoproteins, h-lamp-1 and h-lamp-2. Major sialoglycoproteins carrying polylactosaminoglycan.

Two major lysosomal membrane glycoproteins with apparent Mr approximately 120,000 were purified from chronic myelogenous leukemia cells. These glycoproteins are major sialoglycoproteins containing polylactosaminoglycan and represent approximately 0.1-0.2% of total cell proteins. A monoclonal antibody specific to one of the glycoproteins and polyclonal antibodies specific to the other glycoprotein were obtained. Immunoelectron microscopic examination of HeLa cells revealed that these two glycoproteins mainly reside in lysosomes and multivesicular bodies. Immunoprecipitation experiments showed that a number of different cell lines express these glycoproteins. However, the apparent molecular weights differed between cell lines; this probably represents differences in the amount of polylactosaminoglycan expressed by each cell line. As shown in the following paper (Fukuda, M., Viitala, J., Matteson, J., and Carlsson, S. R. (1988) J. Biol. Chem. 263, 18920-18928) one of the glycoproteins is very homologous to that of a mouse counterpart, m-lamp-1. The human form of this glycoprotein is therefore named human lamp-1 (h-lamp-1), while the other glycoprotein, to which the monoclonal antibody was made, is called human lamp-2 (h-lamp-2). Pulse-chase labeling experiments detected that h-lamp-1 and h-lamp-2 are produced first as precursor forms of 87.5 and 84 kDa, and treatment with endo-beta-N-acetylglucosaminidase H (endo-H) or endo-beta-N-acetylglucosaminidase F (endo-F) reduced their molecular masses to 39.5 and 41.5 kDa, respectively. It was estimated that h-lamp-1 has 18 N-linked saccharides and h-lamp-2 16, based on the results of partial digestions with endo-F. These results indicate that the two lysosomal membrane glycoproteins are extensively modified by N-glycans, and some of these were found to have polylactosaminyl repeats and sialic acid. Human lamp-1 and lamp-2, therefore, serve as good models for understanding polylactosaminoglycan formation and the biosynthesis and processing of polylactosaminoglycan-containing glycoprotein.

Amino Acids↗

Cloning of cDNAs encoding human lysosomal membrane glycoproteins, h-lamp-1 and h-lamp-2. Comparison of their deduced amino acid sequences.

We have isolated and sequenced cDNA clones corresponding to the entire coding sequences of the human lysosomal membrane glycoproteins, lamp-1 and lamp-2 (h-lamp-1 and h-lamp-2). The deduced amino acid sequences indicate that h-lamp-1 and h-lamp-2 consist of 416 and 408 amino acid residues, respectively, and suggest that 27 and 28 NH2-terminal residues are cleavable signal peptides. The major portions of both h-lamp-1 and h-lamp-2 reside on the luminal side of the lysosome and are heavily glycosylated by N-glycans: h-lamp-1 and h-lamp-2 were found to contain 19 and 16 potential N-glycosylation sites, respectively. The findings are consistent with the results obtained by endo-beta-N-acetylglucosaminidase F treatment of h-lamp-1 and h-lamp-2 precursors, described in the preceding paper (Carlsson, S. R., Roth, J., Piller, F., and Fukuda, M. (1988) J. Biol. Chem. 263, 18911-18919). These N-glycosylation sites are clustered into two domains separated by a hinge-like structure enriched with proline and serine in h-lamp-1 or proline and threonine in h-lamp-2. The two domains of h-lamp-1 on each side of the hinge region are homologous to each other, whereas no such homology was detected between the two domains of h-lamp-2. Both proteins have one putative transmembrane domain consisting of 24 hydrophobic amino acids near the COOH terminus, and contain a short cytoplasmic segment composed of 11 amino acid residues at the COOH-terminal end. Comparison of h-lamp-1 and h-lamp-2 sequences reveal strong homology between the two molecules, particularly in the proximity to the COOH-terminal end. It is possible that this portion is important for targeting the molecules to lysosomes. These results also suggest that lamp-1 and lamp-2 are evolutionarily related. Comparison of known lamp-1 sequences among different species, on the other hand, show that human lamp-1 has more similarity to lamp-1 from other species than to human lamp-2. This fact, taken together with the finding that h-lamp-2 lacks repeating domains, suggests that lamp-1 and lamp-2 diverged from a putative ancestor gene in early stages of evolution. These results also suggest that lamp-1 and lamp-2 probably have distinctly separate functions despite the fact that they share many structural features.

Amino Acid Sequence↗

Site-specific glycosylation of human recombinant erythropoietin: analysis of glycopeptides or peptides at each glycosylation site by fast atom bombardment mass spectrometry.

We have previously determined the carbohydrate structure of human recombinant erythropoietin [Sasaki, H., Bothner, B., Dell, A., & Fukuda, M. (1987) J. Biol. Chem. 262, 12059-12076]. The carbohydrate chains are distributed in three N-glycosylation sites and one O-glycosylation site. In order to examine the extent to which protein structure influences glycosylation, we have analyzed the saccharide structures at each glycosylation site (Asn24, Asn38, Asn83, and Ser126) of human recombinant erythropoietin. By high-performance liquid chromatography, we have succeeded in separation of glycopeptides containing different O-linked saccharides to the same peptide backbone. Fast atom bombardment mass spectrometry of the isolated glycopeptides combined with Edman degradation allowed us to elucidate the composition of glycopeptides and the amino acid attachment site. The analysis of glycopeptides and saccharides by fast atom bombardment mass spectrometry and high-performance liquid chromatography provided the following conclusions on N-glycans: (1) saccharides at Asn24 are heterogeneous and consist of biantennary, triantennary, and tetraantennary saccharides with or without N-acetyllactosaminyl repeats; (2) saccharides at Asn38 mainly consist of well-processed saccharides such as tetraantennary saccharides with or without N-acetyllactosaminyl repeats; (3) saccharides at Asn83, on the other hand, are homogeneous in the backbone structure and are composed mainly of tetraantennary without N-acetyllactosaminyl repeats. It was also noted that saccharides at Asn24 are much less sialylated than those at Asn38, although these two glycosylation sites are close to each other. These results clearly indicate that the protein structure and, possibly, the carbohydrate chain at the neighboring site greatly influence glycosylation of a given glycosylation site.

Amino Acid Sequence↗

Alteration of the genes for glycophorin A and B in glycophorin-A-deficient individuals.

Glycophorins A and B are homologous glycoproteins of the red cell membrane which carry the blood-group MN and Ss antigens, respectively, and are encoded by two distinct genes closely linked on chromosome 4, which are probably derived from each other by duplication during evolution. The lack of glycophorin A is associated with the rare phenotype En(a-), indicating individuals who are defective for MN antigens, as well as for the Ena antigens, also located on this glycoprotein. The En(a-) condition is heterogenous and includes two categories of variants exemplified by the Finnish and the English types referred to as En(Fin) and En(UK), respectively. By Southern blot and preliminary genomic clone analyzes we have compared the status of the genes for glycophorins A and B, as well as that of the gene encoding glycophorin C, another unrelated red cell membrane glycoprotein, in the En(a-) variants and in the En(a+) control donors. Our data indicate that the En(Fin) variant is homozygous for a complete deletion of the glycophorin A gene without any detectable abnormality of the genes encoding glycophorins B or C. In the genome of the En(UK) variant, with the presumed genotype Mk/En(UK), and where the Mk condition abolishes the expression of MN and Ss antigens, we have identified several abnormalities of the glycophorin A and B genes, but the glycophorin C gene was unaffected. Our results strongly support the view that in Mk chromosome the glycophorin A and B genes are largely deleted, whereas the En(UK) chromosome probably contains a gene fusion product encoding a hybrid glycoprotein AM-B, composed of the N-terminal portion of a blood group M-type glycophorin A and of the C-terminal portion of glycophorin B. The determination of the 5' and 3' limits of the hybrid gene and elucidation of the mechanism involved will require sequencing of the rearranged DNA of the variant and a full knowledge of the organization of the glycophorin A and B genes.

Blotting, Southern↗

Human T-lymphocyte activation is associated with changes in O-glycan biosynthesis.

The activation of human T-lymphocytes by anti-CD3 antibodies and interleukin-2 results in a marked increase in apparent molecular weight of the major cell-surface sialoglycoprotein. Both forms of the sialoglycoprotein were identified as leukosialin by a monospecific antiserum, and the differences in molecular weight were found to be due to changes in the carbohydrate structures. Our results suggest that resting T-lymphocytes express on leukosialin the disialotetrasaccharides NeuNAc alpha 2----3Gal beta 1----3(NeuNAc alpha 2----6)Gal-NAc-Ser/Thr, whereas activated human T-cells carry on leukosialin exclusively the more complex structures NeuNAc alpha 2----3Gal beta 1----3(NeuNAc alpha 2----3Gal beta 1----4GlcNAc beta 1----6)GalNAc-Ser/Thr. The radical shift in the biosynthetic pathway of O-glycans in activated T-lymphocytes compared to resting cells is apparently caused by a decrease of alpha 2----6 sialyltransferase activity and by the parallel dramatic stimulation of the beta 1----6GlcNAc-transferase. Since both enzymes compete for the same precursor substrate, the coordinate changes in their activities are most likely responsible for the complete change of the carbohydrate structures on leukosialin during the activation of human T-lymphocytes.

Antigens, CD↗

Long-term comparison of oral hypoglycemic agents in diabetic retinopathy. Gliclazide vs. other sulfonylureas.

Gliclazide has been reported to possess the properties of preventing the progression of diabetic retinopathy and of controlling blood glucose levels. This report describes a long-term comparative clinical trial of this agent to assess its efficacy against diabetic retinopathy. One hundred and fifty-nine NIDDM patients with no retinopathy or with simple retinopathy entered this trial. One hundred and nineteen patients receiving other sulfonylurea agents were randomly allocated to two groups (G: gliclazide, SU: other sulfonylureas). Forty patients continued to be treated with diet alone (D group). Finally a total of 60 patients, that is, 21 patients in the G group, 19 patients in the SU group, and 20 patients in the D group, were followed with funduscopic examinations for more than 4 years. The results are summarized as follows. (1) Distribution of background factors between the two drug therapy groups was balanced, but in the D group more male patients and relatively milder cases were involved than in the drug therapy groups. (2) Fasting blood glucose control in the three groups was not significantly different. (3) Funduscopic deterioration was observed less frequently, though not significantly, in the G group than in the other groups. (4) Progression to preproliferative retinopathy was significantly less frequent in the G group than in the SU group. Thus, gliclazide seems to have additional properties compared with other sulfonylurea drugs in preventing deterioration of diabetic retinopathy, and particularly in preventing progression to proliferative retinopathy.

Diabetes Mellitus, Type 2↗

Quantitative studies on proliferative changes of reactive astrocytes in mouse cerebral cortex.

Cell number and proliferation of reactive astrocytes were studied quantitatively in the stabbed cerebral cortex of adult mice, using immunohistochemistry for glial fibrillary acidic protein (GFAP) and [3H]thymidine autoradiography. GFAP-positive astrocytes increased in cell number gradually from 24 to 96 h after stabbing, and their immunoreactivity became intense. The maximum number of GFAP-positive cells was about 4.5 times normal in the layers II-VI of the cortex, whereas it was only 1.5 times normal in the layer I (molecular layer). In contrast to the gradual increase in cell number, no GFAP-positive astrocytes were labeled with [3H]thymidine prior to 48 h after stabbing, in either the layer I or the layers II-VI. Then 3-5% of them were labeled at 72 and 96 h, but very few again after 6 days. By injecting [3H]thymidine successively for 6 days after stabbing, only 17% of GFAP-positive astrocytes of the layer I or the layers II-VI were labeled. These results reveal that, in the cortical layers II-VI, many GFAP-negative source cells initially express much more GFAP-antigen without proliferation and change into GFAP-positive reactive astrocytes. Proliferation of reactive astrocytes is not the major factor for the marked increase in number of them. The cortical layer I would have few GFAP-negative source cells for reactive astrocytes. These source cells may be protoplasmic astrocytes.

Animals↗

A membrane-anchored form but not the secretory form of human chorionic gonadotropin-alpha chain acquires polylactosaminoglycan.

Large polylactosaminoglycans have only been observed linked to membrane proteins. To determine if membrane anchoring of a secretory protein might lead to the addition of polylactosaminoglycan, we have examined the carbohydrate structure on a membrane-anchored form of human chorionic gonadotropin-alpha subunit. This protein was generated by fusing the DNA encoding the human chorionic gonadotropin-alpha subunit to the DNA encoding the membrane-spanning and cytoplasmic domains of the vesicular stomatitis virus glycoprotein. DNAs encoding this hybrid form and the secretory form of human chorionic gonadotropin-alpha were expressed in monkey COS-1 cells using an SV40-based vector. We show here that the parent secretory glycoprotein contains typical Asn-linked complex-type oligosaccharides while the membrane-bound form contains large, heterogenous polylactosaminoglycans. We conclude that membrane anchoring increases the accessibility of the N-linked glycans to the enzymes involved in polylactosamine addition. The inhibitor 1-deoxymannojirimycin blocks addition of the polylactosaminoglycan.

1-Deoxynojirimycin↗

Aldose reductase inhibitor (CT-112) eyedrops for diabetic corneal epitheliopathy.

We treated two diabetic patients with corneal epithelial disorder that resisted conventional medical therapy with topical CT-112 (5-[3-ethoxy-4-pentyloxyphenyl]-2,4-thiazolidinedione), a newly synthesized aldose reductase inhibitor. One patient had developed recurrent corneal erosion after vitrectomy and the other had spontaneously developed superficial punctate keratopathy. The corneal lesion in each patient responded to topical CT-112 in two to four weeks and was almost cleared within two months. A similar corneal lesion recurred in both patients soon after CT-112 was discontinued, but it disappeared again when the drug was resumed.

Aged↗

Histamine H1-receptor in the retina: species differences.

Histamine H1-receptors in membranes of the various mammalian retinas were studied by [3H]mepyramine binding assay. Specific [3H]mepyramine bindings to bovine, pig, dog and human retinas were observed with the dissociation constants (KD), 3.8 +/- 1.2 nM, 1.8 +/- 0.6 nM, 2.6 +/- 0.6 nM and 3.0 +/- 0.9 nM, respectively, which were similar to those found in brains. But there was no detectable specific binding in the guinea-pig and rabbit retinas. The number of binding sites (Bmax) ranged from negligible value to 290.7 +/- 51.7 fmole/mg protein(human retina). Some H1-antagonists acted as potent agents in competing with [3H]mepyramine binding to bovine and pig retinas. These results indicated that histamine H1-receptors exist in some mammalian retina and have similar characteristics to those in brain membranes, but they distributes in the wide difference of the binding capacities among the species, while in brain variations were smaller.

Animals↗

G3m(21) typing by ELISA and dot immunobinding with enzyme-labeled monoclonal anti-G3m(21) antibody.

Simple, rapid methods are described for G3m(21) typing with peroxidase-labeled monoclonal anti-G3m(21) antibody. In G3m(21) typing by ELISA, microtiter wells were coated directly with the test antigen, which was detected with the enzyme-labeled monoclonal antibody. To further simplify the procedure, a dot immunobinding method was developed. The antigen in the test serum applied onto a nitrocellulose membrane was successfully detected with the enzyme-labeled monoclonal antibody. These methods, particularly the dot immunobinding, are suitable for forensic casework because they are rapid and simple and require no technical skill.

Antibodies, Monoclonal↗

Haptoglobin phenotyping by polyacrylamide gel isoelectric focusing and its application to simultaneous typing of serum proteins.

A simple isoelectric focusing method for haptoglobin (HP) typing is described. Serum was pretreated first with C. perfringens neuraminidase (CPN) and then with dithiothreitol (DTT). The treated serum was subjected to polyacrylamide gel isoelectric focusing (PAGIF), and the band patterns were detected by immunoblotting. The method could be successfully applied to HP typing of bloodstains as old as 2 months. A slight modification of it enabled HP, complement component C81, and factor I (IF) to be typed simultaneously. The immunoblotting facilitated preservation of HP patterns. Thus, the PAGIF method for HP typing is suitable for routine use in the forensic laboratory.

Blood Proteins↗

Examination of previous caesarean section scars by ultrasound.

We examined 84 lower segment caesarean section scars by ultrasonography near term. Seventy scars showed good healing with a thickness of the lower uterine segment of more than 3 mm; 14 scars showed poor healing with a thickness of less than 2 mm and loss of continuity. Among 70 patients with good healing, 24 patients delivered vaginally but the remaining 46 patients have had repeat caesarean sections for other obstetric indications. Intraoperative findings in these 46 patients were as follows: Grade I (no thinning of the lower uterine segment), 42; Grade II (thinning and loss of continuity of the lower uterine segment but fetal hair not visible), 4; Grade III (thinning of the lower uterine segment and fetal hair visible), 0. Fourteen patients with poor healing had repeat caesarean sections. Intraoperative findings in these 14 patients were as follows: Grade I, 0; Grade II, 9; Grade III, 5. These results indicate that ultrasound examination detect thinning of the lower uterine segment and may help to determine management.

Adult↗

The effect of cyclosporine on mortality and renal function in living related pediatric kidney transplant recipients.

The outcome, incidence of acute rejection episodes, complications and cyclosporine (CyA) induced nephrotoxicity were studied in 10 pediatric kidney transplant recipients who were grafted from one-haplotype indentical parent with immunosuppression of CyA and prednisolone (Pred). Excellent patient and graft survival could be achieved in this population with low incidences of acute rejection or serious complications as when compared with the results of azathioprine (AZ) treated pediatric patients. With a mean follow-up of 12.9 months (range 1 to 50 months), the patient survival rate was 100 per cent and the graft survival rate was 100, 84, 84 and 84 per cent at 1, 2, 3 and 4 years post transplantation, respectively. Serum creatinine levels in the group were 0.97, 1.17, 1.14 and 1.2 mg/dl at 3, 6, 12 and 24 months post transplantation, respectively. The incidence of treated acute rejection episodes was 20 per cent (2 out of 10) in the CyA-treated children, whereas it was 53 per cent (9 of 17) in the Az-treated children. Five children who had undergone transplant surgery before they were 11 years old displayed linear growth in height after their transplantation. There have been no opportunistic infections, aseptic necrosis or peptic ulcers in this group and cyclosporine nephrotoxicity has not been a serious problem in the pediatric recipients. Only 10 per cent (1 out of 10) of the recipients displayed acute nephrotoxicity and only one recipient has converted from CyA + Pred to CyA + AZ + Pred (Three drug therapy) due to persistent nephrotoxicity.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Interactions of extracellular collagen and corneal fibroblasts: morphologic and biochemical changes of rabbit corneal cells cultured in a collagen matrix.

Corneal fibroblasts, also known as keratocytes are surrounded by an extracellular matrix of collagen in vivo. To understand the physiology and pathology of these corneal fibroblasts, it is important to study their interactions with this extracellular matrix. We cultured rabbit corneal fibroblasts on tissue culture plastic dishes or in a hydrated collagen gel and compared the changes in morphology and mitotic activity. Corneal fibroblasts on plastic dishes were flattened and widely spread, whereas those in collagen gel became spindle-shaped with long processes. Examination with an electron microscope revealed that the corneal fibroblasts in collagen gel formed gap junctions with neighboring cells. Gap junctions were hardly ever observed between corneal fibroblasts cultured on plastic dishes. Corneal fibroblasts cultured in a collagen matrix showed much less incorporation of [3H]thymidine than did corneal fibroblasts cultured on plastic, and this incorporation decreased with increasing concentration of collagen. Our present results suggest that the morphologic and biochemical characteristics of corneal fibroblasts cultured in collagen gel are different from those cultured on plastic.

Animals↗