Kinetic analysis of amyloid fibril formation.
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Amyloid↗
Biomedical subjects
F Gejyo
Publications and source records attributed to F Gejyo.
Lipid-binding proteins in rat and human kidney.
BACKGROUND: The kidney metabolizes actively lipophilic molecules. Several species of lipid-binding proteins (LBPs) have been well characterized, including fatty acid-binding proteins (FABPs), acyl-CoA binding protein (ACBP), sterol carrier protein 2 (SCP2), cellular retinol binding protein (CRBP), and phosphatidylinositol transfer protein (PITP). METHODS: To clarify which LBPs are expressed in isolated rat glomeruli (RG), cultured rat mesangial cells (RMC) and human kidney, RT-PCR, immunoblot analysis and immunohistochemistry were performed. RESULTS: Protein and mRNA expression of heart type (H-) FABP was found in RMC, but not in RG. Immunohistochemistry using antihuman H-FABP antibody revealed that an H-FABP like protein was present in the capillary wall and distal tubules of human glomeruli. Immunoblot analysis using the antibody showed that a 110-kDa protein related to H-FABP was present in human isolated glomeruli but not in any other tissues tested including blood, liver, and heart, and that the 14-kDa protein, H-FABP itself was localized in the distal tubules of human kidney. mRNA for SCP2, ACBP and PITP was detected in RG and RMC. CRBP and mRNA was detected in RG but not RMC. CONCLUSIONS: A variety of lipid-binding proteins are present in rat glomeruli. In human glomeruli, a novel 110-kDa H-FABP-related protein is localized specifically in the capillary wall.
Animals↗
A common mutation of cholesteryl ester transfer protein gene in dialysis patients.
BACKGROUND: In patients on maintenance hemodialysis, a decreased concentration of high-density lipoprotein cholesterol (HDL-C) is an apparent independent risk factor for vascular disease (VD). A common missense mutation of cholesteryl ester transfer protein (CETP) gene, D442G (Asp442 to Gly), increases HDL-C levels, but the mutation may also diminish the activity of reverse cholesterol transport. METHODS: We compared the genotype distribution of the D442G polymorphism and postprandial serum lipid levels between patients with and without VD in 414 hemodialysis patients. RESULTS: Serum levels of total cholesterol and HDL-C did not differ in patients with the mutation [group M (+)] and without the mutation [group M (-)] and in patients with and without VD. However, patients with below median HDL-C levels (< 45 mg/dl) had a significantly higher prevalence of VD than those with above median HDL levels (26.0 vs. 15.2%, P < 0.01). Moreover, in this low-HDL-C subgroup, group M (+) patients had a significantly higher prevalence of VD than group M (-) patients (54.5 vs. 24.4%, P < 0.05). In the subgroup, group M (+) patients with VD had higher levels of total cholesterol and a higher atherogenic index than those without VD, whereas group M (-) patients with VD had lower levels of total cholesterol and a lower atherogenic index than those without VD. CONCLUSIONS: The D442G mutation may be a risk factor for atherosclerotic complications in dialysis patients with HDL-C levels below 45 mg/dl. Atherogenic lipid profiles may promote atherosclerosis in the patients with the mutation, but not in those with no mutation.
Adult↗
Apolipoprotein E phenotypes in hemodialysis patients.
BACKGROUND: Apolipoprotein (apo) E polymorphism consists of three major isoproteins (E2, E3, and E4). Because of their difference in a lipid-modulating effect, the polymorphism has been reported to affect the morbidity of atherosclerosis in general population. Therefore, in hemodialysis (HD) patients, the apo E polymorphism may also modulate serum levels of cholesterol and susceptibility to atherosclerotic vascular disease. METHODS: We determined apo E phenotypes in 493 HD patients and 422 controls. We also investigated vascular risk profile and measured postprandial serum levels of lipids and apos in the dialysis patients. RESULTS: We found a similar phenotype distribution and allele frequency between HD patients and healthy controls. Serum levels of total cholesterol, triglyceride, and apo A I, A II, and C III did not differ significantly among patients with phenotypes apo E2/3, E3/3, and E3/4. Patients with apo E3/4 had significantly lower levels of high-density lipoprotein cholesterol, significantly higher levels of low-density lipoprotein cholesterol (LDL-C), and a higher atherogenic index than those with apo E2/3 (LDL-C, 100 +/- 30 vs. 82 +/- 35 mg/dl, P < 0.01; the index, 3.3 +/- 1.7 vs. 2.3 +/- 1.3, P < 0.01). Patients with apo E3/4 showed a tendency toward higher levels of apo B than patients with apo E2/3 or apo E3/3. Multiple logistic regression analysis revealed that age and diabetes mellitus, but not apo E phenotypes, were independent risk factors for vascular disease. CONCLUSIONS: Apo E polymorphism modulates cholesterol metabolism in dialysis patients but appears to have little association with the prevalence of atherosclerotic complications in the patients.
Age Factors↗
Immunotherapy of disseminated fibrosarcoma in mice using IL-2-producing tumor cells: studies on its mechanism and specificity.
Genetically modified, IL-2-producing tumor cells have been shown to regress in vivo and immunize mice against subsequent challenge with parental tumor. We investigated whether IL-2-producing tumor cells may serve as immunotherapy of established tumors in mice. MCA 205 and MCA 203, weakly immunogenic murine sarcomas of B6 origin, were transfected with the pBMGNeo-mIL-2 vector containing the murine IL-2 cDNA. Mice receiving intraperitoneal injections of the parental sarcoma cells developed ascites and died within 4 weeks. The intraperitoneal injection of IL-2-producing tumor cells significantly prolonged survival and, moreover, significantly reduced the number of established pulmonary metastases. The specificity of this effect was indicated by the unaltered course of disease in mice that were injected with unrelated IL-2-producing tumor cells. FACS analysis of peritoneal cells obtained from treated mice showed a predominance of Vbeta3-positive cells. In a 4 h 51Cr release assay, these Vbeta3-positive cells exhibited tumor-specific cytotoxicity and also nonspecific effector cells are shown to be involved in tumor rejection.
Animals↗
Significance of serum pepsinogens and their relationship to Helicobacter pylori infection and histological gastritis in dialysis patients.
BACKGROUND: Previous investigations reported that patients undergoing dialysis therapy had significantly higher serum pepsinogen (PG) levels than patients with normal renal function. However, in dialysis patients, the relationship between serum PG levels and Helicobacter pylori infection remains unknown. METHODS: Sixty three maintenance dialysis patients (54 haemodialysis and nine continuous ambulatory peritoneal dialysis) who required endoscopic examination were enrolled in the study. Sixty four age- and sex-matched patients with normal renal function served as controls. We performed endoscopic examination and obtained both the gastric antral and corpus mucosa for histopathological evaluation and H. pylori identification. Twenty three patients on dialysis underwent H. pylori eradication therapy. RESULTS: In dialysis patients, H. pylori-positives had significantly higher serum PG II levels than H. pylori-negatives (26.6+/-21.5 vs 14.1+/-7.1 ng/ml, P<0.05), but no significant difference was found in serum PG I between H. pylori-positives and H. pylori-negatives (228.8+/-158.5 vs 179. 4+/-113.5 ng/ml). There was no significant difference in serum PG II between dialysis patients and controls (19.9+/-16.5 vs 18.6+/-14.9 ng/ml), while serum PG I levels were significantly higher in dialysis patients than in controls (201.7+/-136.8 vs 77.6+/-85.8 ng/ml, P<0.05). Serum PG II levels, but not those of PG I, significantly correlated with the inflammation and activity scores of antrum in dialysis patients, and these scores were highly influenced by H. pylori infection. Dialysis patients in whom H. pylori was eradicated successfully showed significant reductions of serum PG II levels but not of PG I. CONCLUSIONS: In dialysis patients, high serum levels of PG II, but not PG I, are significantly related to H. pylori infection and mucosal inflammation. A significant decrease in serum PG II levels could be used as a predictor of the eradication of H. pylori infection in dialysis patients.
Aged↗
High frequency of antibody activity against ribosomal protein S10 in anti-Sm sera from patients with systemic lupus erythematosus.
This study was carried out to clarify the frequency of detection of antibody activity to ribosomal protein S10 (anti-S10) in patients with systemic lupus erythematosus (SLE) with anti-Sm antibodies (anti-Sm), and clinical differences between anti-Sm-positive SLE patients with and without anti-S10. Twenty-seven of 31 serum samples containing anti-Sm reacted with ribosomal protein S10 along with Sm core proteins B/B' and D (87.1%). Four serum samples containing anti-Sm against only B/B' but not D did not react with S10 (12.9%). Patients who had both anti-Sm and anti-S10 showed lower serum complements levels, high frequency of skin lesion and anti-double-stranded DNA antibody. Many anti-Sm antibodies may recognize B/B', D, and S10 simultaneously, and such antibodies may appear in active disease.
Antibody Specificity↗
The leukotriene B4 receptor antagonist ONO-4057 inhibits nephrotoxic serum nephritis in WKY rats.
To evaluate the role of leukotriene B4 (LTB4) in glomerulonephritis, this study was conducted to examine whether ONO-4057, an LTB4 receptor antagonist, moderated nephritis caused by the injection of nephrotoxic serum (NTS) into Wistar-Kyoto rats. Rats were given intraperitoneal injections of ONO-4057 or phosphate-buffered saline 24 h before the injection of NTS. These rats subsequently received equal doses of ONO-4057 or phosphate-buffered saline 3 h and 1, 2, 3, 4, 5, and 6 d later. Compared with the control groups, ONO-4057 treatment significantly reduced proteinuria and hematuria, suppressed the glomerular accumulation of monocytes/macrophages, and reduced the formation of crescentic glomeruli in a dose-dependent manner. These results suggest that LTB4 is responsible for the crescentic formations and renal dysfunction associated with NTS nephritis. The LTB4 receptor antagonist ONO-4057 may thus be beneficial in the treatment of crescentic glomerulonephritis.
Animals↗
A cholesteryl ester transfer protein gene mutation and vascular disease in dialysis patients.
Among patients undergoing maintenance hemodialysis, a decreased high-density lipoprotein cholesterol (HDL-C) concentration is among the most common abnormalities of lipid metabolism and apparently is an independent risk factor for vascular disease. A common missense mutation of cholesteryl ester transfer protein gene, D442G (Asp 442 to Gly), increases HDL-C levels through the reduced activity of cholesteryl ester transfer from HDL to VLDL, but the mutation also may lead to reduced activity of reverse cholesterol transport. To investigate the effect of the D442G polymorphism on atherosclerotic complications in dialysis patients, the genotype and allele frequency of the polymorphism were determined in 414 unselected dialysis patients and 220 control subjects, and postprandial serum lipid levels were measured in the dialysis patients. A similar genotype distribution was found between hemodialysis patients and healthy control subjects, and in dialysis patients with and without vascular disease. Serum levels of total cholesterol and HDL-C did not differ between patients with and without the mutation and in patients with and without vascular disease. However, patients with sub-median HDL-C levels (<45 mg/dl) had an independent odds ratio of 1.8 for vascular disease (95% confidence interval, 1.04 to 3.2; P < 0.05). In this low-HDL-C subgroup, patients with the D442G mutation had a significantly higher prevalence of vascular disease than those with no mutation (54.5% versus 24.4%; P < 0.05), and an independent odds ratio of 4.9 (95% confidence interval, 1.05 to 22.65; P < 0.05). In conclusion, the D442G mutation is an independent risk factor for atherosclerotic complications in dialysis patients with HDL-C levels below 45 mg/dl.
Adolescent↗
Elevation of serum CA19-9 levels in benign diseases.
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CA-19-9 Antigen↗
Structural analysis of the amyloidogenic kappa Bence Jones protein (FUR).
Patients with systemic amyloidosis associated with multiple myeloma (AL-amyloidosis) exhibit immunoglobulin light chains and fragments which have been identified as amyloid protein. Since a relatively small proportion of patients with multiple myeloma develop AL-amyloidosis, comparison of the amino acid sequence of the amyloidogenic and non-amyloidogenic immunoglobulin light chains and the structural characterization of the amyloid proteins are required to understand the relationship between structure and amyloidogenicity. We determined the primary structure of a kappa I-type Bence Jones protein obtained from a patient (FUR) who had systemic AL-amyloidosis associated with multiple myeloma. We identified eight amino acid replacements unique to this patient among the amyloidogenic kappa I-light chains, and which are also rare among the known kappa type light chains of humans. Three of these substitutions were within the framework regions and may act to destabilize the structure to promote a putative amyloidogenic conformation. In contrast to light chain fragments in the urine, which were processed in the variable region, mass spectrometric analysis of the fibril proteins isolated from lingual amyloid deposits in this patient, revealed that they were all truncated within the constant region and corresponded to residues 1-125, 1-144, and 1-210. Inspection of the predicted three-dimensional model of this protein suggested that these fragments may be generated by a protease specific for the N-terminal sides of basic amino acids. These findings suggest that amino acid substitutions at highly conserved residues may convert non-amyloidogenic to amyloidogenic immunoglobulin light chain proteins.
Aged↗
Modification of beta 2-microglobulin with D-glucose or 3-deoxyglucosone inhibits A beta 2M amyloid fibril extension in vitro.
beta 2-microglobulin (beta 2M) is a major constituent of amyloid fibrils (fA beta 2M) deposited in patients with A beta 2M amyloidosis. Recently, advanced glycation end products (AGE) of beta 2M and fA beta 2M have been suggested to play an important role in the pathogenesis of A beta 2M amyloidosis. We first characterized the states of AGE modification of fA beta 2M. Western blot analysis with a monoclonal anti-AGE antibody showed that purified fA beta 2M was naturally modified with AGE. Immunohistochemical studies of amyloid-deposited tissue have revealed a patchy distribution of the AGE-modified area in the amyloid deposits. Then we modified beta 2-m either with D-glucose or with 3-deoxyglucosone (3-DG) and investigated the effect of these modification on fA beta 2M extension in vitro, using the recently established first-order kinetic model of fA beta 2M extension in vitro. Western blot analysis and enzyme linked immunosorbent assay with a monoclonal anti-AGE antibody showed that these sugar-modified beta 2M contained AGE. During the incubation of fA beta 2M with native beta 2-m at 37 degrees C, the fluorescence of thioflavin T increased without a lag phase and proceeded to equilibrium. On the contrary, only a slight increase in fluorescence was observed during the incubation of fA beta 2M with sugar-modified beta 2M. Moreover, sugar-modified beta 2M exhibited a dose-dependent inhibitory effect on the extension reaction of fA beta 2M with native beta 2M. These results may suggest that in some in vivo situations, the modification of beta 2-m with AGE could play an inhibitory role for the formation of fA beta 2M.
Amyloid↗
[Pranoprofen-induced lung injury manifesting as acute eosinophilic pneumonia].
A 48-year-old man was admitted to our hospital complaining of fever, dyspnea, and cough. He had been treated with pranoprofen and antibiotics by an outpatient clinic for the preceding 4 days. Chest X-ray films revealed Kerley B lines, perivascular cuffing, and hilar haze with pleural effusion in both lungs. Chest computed tomographic films showed non-segmental patchy infiltrates, and thickening of bronchovascular bundles and interlobular septa. Laboratory data showed eosinophilia in peripheral blood (28%) and severe hypoxemia (PaO2:60 torr). Bronchoalveolar lavage fluid disclosed an increased total cell count, eosinophils (39%), and CD 4/CD 8 ratio (2.1). Microscopic examination of transbronchial lung biopsy specimens showed infiltration of eosinophils and mononuclear cells into alveolar wall's and spaces. Acute eosinophilic pneumonia was suspected on the basis of Allen's diagnostic criteria (N Engl J Med: 1989). After discontinuation of pranoprofen, the patient's clinical symptoms, laboratory data, and chest X-ray findings improved rapidly without steroid therapy. A leukocyte migration test (LMT) for pranoprofen was positive and a challenge test for smoking was negative. An environmental provocation test in the patient's home gave negative results. A challenge test for pranoprofen was not performed due to the lack of informed consent. Based on these findings, our diagnosis was pranoprofen-induced lung injury manifesting as acute eosinophilic pneumonia.
Acute Disease↗
[The diagnostic role of the methacholine inhalation challenge in adult patients with chronic persistent cough].
Chronic persistent cough (CPC) is a common medical problem. We determined the value of the methacholine inhalation challenge (MIC) in the evaluation of CPC. We also sought other clinical factors that affect MIC. Patients were selected for the study if 1) CPC was the only presenting symptom, 2) a current roentgenogram did not contribute to the diagnosis, and 3) spirometry revealed a normal FEV1. We measured the minimum dose of methacholine (bronchial sensitivity, Dmin) by the "Asthograph" method. We determined the correlation between log Dmin and demographic and clinical variables, i.e. age, %FVC, %FEV1, FEV1%, %V50, %V25, eosinophil count in peripheral blood, and serum IgE level. The causes of CPC in 51 patients (20 men and 31 women, mean age 41 years) were cough-variant asthma in 29 patients, postinfectious persistent cough in 13 patients, atopic cough in 6 patients, and others in 3 patients. Log Dmin significantly but weakly correlated with %V25 (4 = 0.31, p = 0.02). The sensitivity and specificity of Dmin (< 10 units) in diagnosing cough-variant asthma was 93% and 87%, respectively. Demographic or clinical variables other than Dmin were not useful for the diagnosis of cough-variant asthma. We conclude that MIC is useful for the differential diagnosis of CPC while the usefulness is limited in some cases.
Adult↗
Accumulation of aberrant Y chromosomes in gamma-ray-induced thymic lymphomas lacking p53.
Male F(1) hybrids between MSM mice carrying a deficient p53 allele and BALB/c mice were irradiated with gamma-rays, and 80 thymic lymphomas were obtained, 46 of which developed in mice carrying the deficient p53 allele. Because the Y chromosome contributes little to cellular function, the stability of the Y chromosome in the tumors was assessed by polymerase chain reaction by examining three genes: Smcy and Sry on the short arm and Sts in the pseudoautosomal region of the long arm of the Y chromosome. Twenty-one lymphomas had lost one or two genes, probably as a result of mitotic recombination or interstitial deletion, whereas no lymphomas had lost all three genes. The p53 status of the lymphomas was determined by genotyping and allelic loss analysis; 34 had retained two wild-type p53 alleles, suggesting normal function; 34 had lost both alleles, indicating loss of function; and the other 12 had at least one wild-type p53 allele, so their p53 status was unclear. Compilation of these data revealed that changes in the Y chromosome were detected in only two of the 34 lymphomas retaining functional p53 but in 18 of the 34 lymphomas lacking p53 function, suggesting that p53 deficiency leads to an increase in the accumulation of radiation-induced aberrant chromosomes. This is consistent with our previous result from analysis of the inactive X chromosome. In contrast, a decrease in the fidelity of mitotic transmission in p53-deficient lymphomas was not noted for the Y chromosome.
Abnormalities, Radiation-Induced↗
[A case of occupational asthma due to cyanoacrylate].
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Adhesives↗
[Two cases of silicosis exhibiting MPO-ANCA associated disorder].
We reported two cases of silicosis exhibiting MPO-ANCA associated disorder. Case 1 was a 69 year-old man with silicosis and chronic interstitial pneumonia. He was admitted because of fever, dry cough, left chest pain, dyspnea and body weight loss. He was diagnosed as acute exacerbation of interstitial pneumonia, pericarditis and gastrointestinal bleeding. Case 2 was a 67 year-old man with silicosis. He repeated attack of fever, hoarseness, dysphagia and headache. The cell counts of cerebrospinal fluid increased and the thickness of cerebellar tent and left dura mater was observed in the brain MRI. Therefore, he was diagnosed as pachymeningitis and neuropathy of cranial nerves. Both cases were complicated by silicosis and the laboratory findings showed high serum levels of P-ANCA, ANA and rheumatoid factor and inflammatory responses, indicating they were suspected vasculitis. The two cases were treated by steroid and immunosuppressive therapy and had good clinical response. Silicosis may affect multiple organ involvement associated with P-ANCA.
Aged↗