Progressive blurring of vision in both eyes.
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Adult↗
Biomedical subjects
A Kondo
Publications and source records attributed to A Kondo.
Prominent roles of secondary anchor residues in peptide binding to HLA-A24 human class I molecules.
The binding capacity of large sets of peptides corresponding to naturally occurring sequences and carrying previously defined A24-specific motifs was analyzed. It was found that only a minority (9-25%) of the motif-carrying peptides bound the relevant HLA-A molecule with good affinity (IC 50% < or = 50 nM), while the majority of them bound only weakly or not at all (IC 50% > or = 500 nM). By correlating the presence of specific residue types at each position along the peptide sequence with average binding affinity, the prominent influence of specific secondary interactions (secondary anchor residues) was revealed. Moreover, secondary interactions appeared to be size-dependent in that the specific effects detected differed in 9-mer and 10-mer peptide sets. Based on these observations, A24-specific refined motifs were also established for both 9-mer and 10-mer ligands, and their merit was verified by testing the binding capacity of independent sets of synthetic peptides. Such refined motifs should facilitate accurate prediction of potential A24-restricted peptide epitopes. It was also noted that certain crucial secondary interactions appear to be remarkably similar in the case of A24 and other HLA-A molecules previously analyzed (A*0201, A3, A11, and others). This may reflect contributions to binding affinity of relatively invariant residues located within the polymorphic pockets of the HLA binding groove.
Alleles↗
Enhanced transglycosylation activity of Arthrobacter protophormiae endo-beta-N-acetylglucosaminidase in media containing organic solvents.
The transglycosylation activity of endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (endo-A) was enhanced by inclusion of organic solvents in the reaction mixture. In aqueous solution, the transglycosylation yield relative to starting substrate was 32% using Man9GlcNAc2Asn as donor and 0.5 M GlcNAc as acceptor. However, in the media containing 30% (v/v) acetone, dioxane, N,N-dimethylformamide, or dimethyl sulfoxide with 0.5 M GlcNAc as acceptor, the transglycosylation attained yields of 89, 13, 28, and 75%, respectively, as analyzed by high performance anion exchange chromatography. The enzyme was stable in media containing up to 30% acetone, 30% dimethyl sulfoxide, or 20% N,N-dimethylformamide at 37 degrees C for at least 30 min. The acceptor (GlcNAc) concentration must be greater than 0.2 M for efficient transglycosylation. Electrospray mass spectrometry analysis of the transglycosylation product obtained in 30% acetone with Man5GlcNAc2Asn as donor and methyl alpha-2-acetamido-2-deoxy-D-glucopyranoside as acceptor showed a mass ion of m/z 1249.4, consistent with the expected molecular weight. Analysis by 1H NMR of the product revealed that transglycosylation occurred at the C-4 of GlcNAc and the linkage was of the beta-configuration. In the acetone-containing medium, Glc, Man, 2-deoxy-Glc, and methyl alpha-D-GlcNAc can serve as a good acceptor as GlcNAc. Less favorable acceptors are xylose, fructose, 6-deoxy-Glc, and 3-O-methyl-D-glucose. On the other hand, GalNAc, Gal, allose, and 3-deoxy-Glc could not serve as acceptors of the enzyme transglycosylation.
Acetylglucosamine↗
Synthesis of neoglycoconjugates by transglycosylation with Arthrobacter protophormiae endo-beta-N-acetylglucosaminidase. Demonstration of a macro-cluster effect for mannose-binding proteins.
The transglycosylation activity of endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (endo-A) can be enhanced dramatically by inclusion of organic solvent in the reaction mixture (see accompanying article; Fan, J.-Q., Takegawa, K., Iwahara, S., Kondo, A., Kato, I., Abeygunawardana, C., and Lee, Y. C. (1995) J. Biol. Chem. 270, 17723-17729). This finding was extended to synthesis of important intermediates for preparation of neoglycoconjugates. When 0.2 M GlcNAc-O-(CH2)6NH2, GlcNAc-O-CH2CH = CH2, GlcNAc-O-(CH2)3-CH = CH2, GlcNAc-O-(CH2)3NHCOCH = CH2, GlcNAc-S-CH2CN, GlcNAc-S-(CH2)3CH3, or GlcNAc-S-CH2-CONHCH2CH(OMe)2 were used as acceptors in 30% acetone-containing media, the transglycosylation was accomplished with about 80% yield. The transglycosylation yields to benzyl beta-GlcNAc (67%), 4-methyl-umbelliferyl beta-GlcNAc (66%), p-nitrophenyl beta-GlcNAc (33%), and (GlcNAc-beta-S-CH2CH2CH2)2 (43%) were lower, because their poor solubilities allowed only 0.05 M or lower concentrations in the reaction mixture. A micromole-scale synthesis of Man9GlcNAc2-O-(CH2)3-NHCOCH = CH2 (Man9GlcNAc2-NAP) was accomplished with 90% yield, and the structure of the transglycosylation product was confirmed by 1H NMR. Man9GlcNAc2-NAP was co-polymerized with acrylamide. The ratio of sugar side chain to acrylamide in this glycopolymer was 1:44 and the molecular weight of glycopolymer was estimated to be between 1,500,000 and 2,000,000 by high performance gel filtration chromatography. The glycopolymer was shown to be a much more efficient inhibitor of binding by recombinant rat mannose binding protein-carbohydrate recognition domains (MBP-CRD) from serum (I50 = 3.5 microM Man9GlcNAc2-sugar chain) and liver (I50 = 74.5 nM) than soybean agglutinin.
Acetylglucosaminidase↗
Are advanced glycation end-products associated with amyloidosis in Alzheimer's disease?
Recent studies have suggested that advanced glycation end-products (AGE) of the Maillard reaction are associated with amyloidosis in Alzheimer's disease. To evaluate this possibility, the present immunohistochemical study was undertaken to locate AGE in cerebral cortices of Alzheimer's disease, using a monoclonal antibody specific for AGE-proteins. Deposits of beta-amyloid protein within cores of classic senile plaques and vascular walls in amyloid angiopathy showed no AGE-positive reaction, while primitive plaques, coronas of classic plaques and some glial cells were positive for AGE. These findings are inconsistent with the suggestion that AGE may be involved primarily in amyloidosis in Alzheimer's disease.
Aged↗
Infiltration of dendritic cells into regional lymph nodes in gastric cancer.
BACKGROUND: Dendritic cells (DC), including epidermal Langerhans cells, are potent antigen-presenting cells that can carry and present tumor antigens to helper T-cells. An immunohistochemical study was performed to clarify the relationship between the extent of infiltration by DCs in primary gastric cancer and that in the regional lymph nodes. METHODS: Paraffin blocks were prepared for staining with antibody against S-100 protein in 121 cases of gastric cancer. Infiltration of S-100 protein-positive DCs was evaluated in the primary tumor and in the peritumoral, primary, secondary, and tertiary nodes. RESULTS: The extent of infiltration by DCs into the regional lymph nodes decreased significantly with an increasing distance of the nodes from the primary tumor. Correlation of the extent of such infiltration was observed among the peritumoral, primary, secondary, and tertiary nodes. However, the extent of infiltration into the primary tumor did not correlate with that into the primary, secondary, and tertiary nodes. Infiltration by DCs of the peritumoral nodes correlated with that of the tumor, particularly when lymph node metastasis was absent. There was no significant difference in the extent of infiltration into the peritumoral nodes even when lymph nodes were involved. However, infiltration of DCs increased in the primary and secondary nodes when the primary nodes were involved. CONCLUSION: Infiltration of DCs may be regulated in the primary lesion of gastric cancer. The peritumoral lymph nodes serve as transmitters of DCs from the primary tumor to the regional lymph nodes. DCs in the regional lymph nodes are important for establishing immunologic defense mechanisms in cases of gastric cancer when metastasis is absent or limited to the primary nodes.
Dendritic Cells↗
Synthesis of neoglycoproteins using oligosaccharide-transfer activity with endo-beta-N-acetylglucosaminidase.
We describe a novel method for the enzymatic synthesis of neoglycoproteins. Endo-beta-N-acetylglucosaminidase from Arthrobacter protophormiae (Endo-A) had high levels of transglycosylation activity. The enzyme activity of Endo-A was markedly increased by adding 4-L-aspartyl-glycosylamine (GlcNAc-Asn) to the reaction mixture. Digesting (Man)6(GlcNAc)2 with the enzyme in the presence of GlcNAc-Asn gave a mixture of hydrolytic ((Man)6GlcNAc) and transglycosylic ((Man)6(GlcNAc)2-Asn) products. By means of transglycosylation, (Man)6GlcNAc was transferred en bloc to the partially deglycosylated ovalbumin glycopeptide (EEKYN(GlcNAc)LTSVL) concomitant with the hydrolysis of (Man)6-GlcNAc)2Asn. The structure of the transglycosylation product was designated as (Man)6(GlcNAc)2-peptide by amino acid composition and sequence analysis as well as ion mass spectrometry. The enzyme also transferred oligosaccharide to partially deglycosylated ribonuclease B (GlcNAc-protein) during the hydrolysis of (Man)6-(GlcNAc)2Asn. Native ribonuclease B had (Man)5-9 (GlcNAc)2 as its heterogeneous N-linked sugar chains. High performance liquid chromatography showed that all of the N-linked sugar chains of the synthetic neoribonuclease of the pyridylamino derivatives were modified to (Man)6(GlcNAc)2.
Amino Acid Sequence↗
Protein substrates and heat shock reduce the DNA-binding ability of Escherichia coli Lon protease.
Interaction between the fusion protein MBP-Lon, formed by maltose-binding protein and Lon protease, and the plasmid pBR322 was studied to clarify the DNA-binding behavior of the Lon protease. Since the MBP-Lon fusion protein that was bound to the plasmid was strongly adsorbed by amylose resin, complex formation and dissociation were determined by quantifying the unadsorbed plasmid using agarose gel electrophoresis. The autolysis of MBP-Lon fusion protein was suppressed when the protein was bound to the plasmid. The plasmid was completely dissociated from MBP-Lon fusion protein by the addition of the protein substrates of Lon protease (i.e. alpha-casein and denatured bovine serum albumin). In addition, at high temperatures, MBP-Lon fusion protein lost its plasmid-binding ability, although it fully retained ATP-dependent protease activity. These results suggest that Lon protease loses DNA-binding ability when cells are exposed to abnormal conditions and the amount of damaged proteins increases. On the other hand, DNA probably plays an important role in controlling the Lon protease activity in cells under normal conditions by entrapping the enzyme.
ATP-Binding Cassette Transporters↗
Renal cysts and associated renal tumours in male ddY mice injected with ferric nitrilotriacetate.
In experiments using ferric nitrilotriacetate (Fe-NTA) as a renal carcinogen, multiple renal cysts are often observed in addition to renal tumours. In the present study, we used 3-week-old male ddY mice and examined the relation between renal cysts and cancer development. Four months after the start of Fe-NTA administration, we observed cysts in the renal cortex in all Fe-NTA-treated mice, but not in Fe-free NTA-treated mice. Three types of cysts were observed, but only those which originated from the renal proximal tubules showed multilayered or papillary growth of cyst epithelial cells. Using histochemical staining, we found a cyst formation-tumour induction sequence, and the supposed cystic-papillary tumour induced by Fe-NTA was of proximal tubular cell origin. We also found that the minimum dose of Fe-NTA capable of inducing renal tumours in ddY mice was 10 mg of iron/kg/day, four times in 2 weeks.
Animals↗
Spongy degeneration in the zitter rat: ultrastructural and immunohistochemical studies.
Pathological changes in the grey matter of the zitter rat were examined by electron microscopy and immunohistochemistry to investigate the pathogenesis of spongy degeneration. Vacuole formation was first detected in the pons and the outer thalamus at 2 weeks of age. The vacuoles arose from the periaxonal or inter-myelinic spaces as well as the cytoplasm of some oligodendrocytes or astrocytes. With increasing age, some dendrites and the cytoplasm of neurons developed an electron lucent area with sparse organelles and the vacuoles occasionally fused together. Although spongy degeneration gradually extended to the entire CNS, no inflammatory or phagocytotic cell infiltration and no viral particles were detected. Glial fibrillary acidic protein immunoreactivity increased transiently in the vacuolated areas from 2 to 15 weeks of age (maximal at 7 weeks of age). Although zitter rats older than 65 weeks showed some reactive astrocytes in vacuolated areas, their numbers and the intensity of immunostaining decreased with advanced vacuolation suggesting astrocytic hypofunction in response to tissue damage. Immunoreactivity for synaptophysin was weaker in the zitter rats than in the control rats throughout the observation period, which suggested that synapse formation was disturbed in the zitter rats, probably due to a combination of hypomyelination and vacuole formation in the grey matter. These findings suggest that an unknown genetic abnormality, probably related to cell membrane biosynthesis or cell-to-cell interactions, produces both hypomyelination and spongy degeneration in the zitter rat.
Aging↗
Apolipoprotein E mRNA in the brains of patients with Alzheimer's disease.
To clarify the role of apolipoprotein E (apoE) in the pathophysiology of Alzheimer's disease (AD), we used an RT-PCR method to investigate apoE and glial fibrillary acidic protein (GFAP) mRNA expression in the brain. ApoE mRNA was significantly more abundant in AD (0.379 +/- 0.191, mean +/- SD) than in control (0.125 +/- 0.073, p < 0.05) brain tissue, but in AD it was decreased in relation to the apoE-epsilon 4 gene dosage. The GFAP mRNA content also was greater in AD (5.96 +/- 2.94) than in control (3.80 +/- 2.78) tissue, and in AD showed an increase relative to the apoE-epsilon 4 gene dosage. AD patients who had long survival times showed high expression of apoE and low expression of GFAP. These results suggest that apoE suppresses the progression of AD, including gliosis, in the brain.
Adult↗
Changes in rat bladder function following exposure to pain and water stimuli.
Changes in rat bladder function following the exposure to physical stress were studied in vitro. Rats were divided into two stress groups and two control groups and maintained for 6 months under specific conditions. The stress groups, consisting of animals subjected to water or pain stress and control groups were kept in cages floored with wooden chips or wire net. The body weight of the stressed groups was significantly lower than that of the controls. Gastric ulcer occurred in none of the groups. The detrusor response of the water group to acetylcholine was significantly greater than that of the two control groups. In the pain group, the contractile response was induced by norepinephrine. In the other three groups, however, norepinephrine evoked a relaxation of muscle strips. The contractile response of the bladder to both serotonin (5-hydroxytryptamine) and ATP (adenosine 5'-triphosphate) did not differ between the four groups.
Acetylcholine↗
Treatment of stress incontinence by vaginal cones: short- and long-term results and predictive parameters.
OBJECTIVE: To evaluate prospectively the short- and long-term results of treatment with vaginal cones for women with urinary stress incontinence and to assess predictive parameters. PATIENTS AND METHODS: Fifty women (mean age 49 years, range 28-76) with differing severities of stress incontinence (mean parity 2.4 and mean 60-min pad-test 20.7 g) were treated with cones for 15 min twice a day for 8 weeks. Treatment results were evaluated immediately after and at a mean of 3 years after the treatment. Parameters were analysed to determine those with predictive value for a successful outcome. RESULTS: Physiotherapy was assessed as being successful, i.e. a complete cure or a reduction of > 50% of the original severity, in seven patients (14%), while in 43 patients (86%) the treatment failed. After 3 years, 13 (30%) reported that the treatment was successful, 27 (61%) reported failure and four (9%) underwent surgery for stress incontinence. Those with lesser amounts of urinary loss and those with less frequent incontinence would be most likely to benefit from treatment with vaginal cones. CONCLUSION: The treatment had a low success rate and we recommend that the vaginal cones should be used only for those with a slight or moderate degree of stress incontinence.
Adult↗
Effects of magnesium ions on detrusor contraction in rat.
Contraction of smooth muscle including detrusor is initiated by an increase in the concentration of intracellular free calcium ions. Magnesium affects the translocation of calcium ions through the smooth muscle cell membrane. The effect of magnesium ions on detrusor contraction was investigated in vitro using the rat detrusor muscle. Detrusor contractility caused by intramural nerve stimulation increased in a magnesium-free solution but decreased in a high-magnesium solution (MgCl2 5 mM). Cumulative addition of MgCl2 suppressed the detrusor response induced by field stimulation dose-dependently, and 30 mM MgCl2 completely eliminated it. Mg ion also suppressed atropine-resistant detrusor contraction in a dose-dependent manner. After blocking nerve-mediated detrusor contractility with tetrodotoxin, Mg ions inhibited spontaneous detrusor contractions and reduced tonus of the muscle strips. Mg ions suppressed the detrusor contraction induced by carbachol and potassium. The effect of Mg ions on detrusor contraction was enhanced by verapamil but inhibited by Bay-K8644. These results suggest that Mg ions suppress detrusor muscle contractility through an inhibitory mechanism acting on calcium channels in the smooth muscle cell membrane.
3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
Hemifacial spasm in childhood and adolescence.
Hemifacial spasm (HFS), a hyperactive dysfunction of the facial nerve, is rarely seen in young people. Between 1984 and 1994, we treated 924 patients with HFS by microvascular decompression at our institution. Of these, 8 (0.9%) were younger than 30 years. In most of the older patients with HFS, the offending artery which compresses the root exit zone was elongated, redundant, and focally arteriosclerotic as a result of hemodynamic effects due to aging or hypertension. On the other hand, the offending artery did not exhibit such characteristic changes of the vasculature in children and adolescents with HFS. In all of the young patients who underwent initial microvascular decompression at our clinic, the arachnoid membrane around the facial nerve was thickened and encased the artery, resulting in compression of the root exit zone of the facial nerve. Such thickening of the arachnoid surrounding the offending vessel may play an important role in the pathogenesis of HFS by trapping and encasing the artery to compress the root exit zone, particularly in the young patients.
Adolescent↗
Intraorbital malignant lymphoma presenting with tumor stain on angiography--case report.
A 58-year-old male presented with a 1 month history of left retro-orbital pain and diplopia. Computed tomography demonstrated an isodense intraorbital tumor with slight homogeneous enhancement. Magnetic resonance imaging showed the tumor was isointensity on T1-weighted imaging, slightly high intensity on T2-weighted imaging, and slightly enhanced by gadolinium-diethylenetriaminepenta-acetic acid. Left external carotid angiography showed a tumor stain fed from the branches of the left internal maxillary artery. The tumor was partially removed. The histological diagnosis was malignant lymphoma. Tumor staining is rare in intraorbital malignant lymphoma and is not adequate for differential diagnosis of intraorbital tumors, so biopsy is essential.
Carotid Artery, External↗
[Needle suspension of the bladder neck for stress urinary incontinence: surgical results of 394 patients operated on with quantitative procedures].
We have investigated surgical results of quantitative suspension of the bladder neck for stress urinary incontinence. Three hundred ninety-four female patients suffering from stress incontinence have been operated on with Stamey's or Gittes' procedures during the past 8 years. While the bladder neck was elevated by quantifying tension of nylon threads in 84 patients, 310 patients subsequently were operated on by quantifying both tension and length of nylon loops. A follow-up period averaged 51 months for a group of the Stamey's and 19 months for a group of Gittes' procedures. Postoperative continence rate was defined by patients' subjective evaluation. Those whose nylon loops were quantified as from 130 to 149 mm attained the highest continence rate, which was not related to age or severity of incontinence. Postoperative difficulty in urination was less in those who had nylon loops of 130 to 149 mm, and was more in those over 60 years of age. Eighty-eight percent of the patients stated very much satisfied or satisfied with the surgery they had undergone. Continence rate was 78% for those operated on with the Stamey's (51 months later) and 69% with the Gittes' procedures (19 months later). The 7-year continence rate was 77% for the former and the 3-year continence rate was 38% for the latter, indicating that the Stamey's procedure was significantly more useful than the Gittes' procedure. Postoperative complications were encountered with 17% of the patients. We conclude that quantitative suspension of the bladder neck is of value to obtain the high success rate of the needle suspension procedure.
Adult↗
Urodynamic study of storage and evacuation of urine in patients with a urethral Kock pouch.
PURPOSE: The urodynamics of pouch-urethra function were investigated in patients with a urethral Kock pouch to understand mechanisms involved in the storage and evacuation of urine, and elucidate any problems of long-term outcome. MATERIALS AND METHODS: Urodynamic evaluation was performed in 18 male patients who underwent bladder replacement with a urethral Kock pouch following radical cystectomy. RESULTS: Good urinary continence was achieved with normal frequency of voiding. On urodynamics pressure within the pouch remained low during the storage phase (mean 33.2 cm. water) but markedly increased during the evacuation of urine (mean 77.3 cm. water). In 8 patients (44%) extremely high pressure within the pouch (80 to 150 cm. water) was noted at voiding. Clean intermittent self-catheterization was initiated in a patient with high pressure within the pouch at voiding in whom pouch-ureter reflux developed 7 months postoperatively. The external urethral sphincter was impaired to some extent postoperatively but it contracted in response to filling of the pouch with a marked increase in urethral pressure from a mean of 31.6 to 66.3 cm. water. CONCLUSIONS: Urodynamic and radiological studies will be necessary periodically since high pressure within the pouch at voiding might jeopardize the antireflux mechanism, leading to reflux and renal impairment.
Adult↗