Quantitative analysis of serum amyloid A protein isotypes]

We examined the isotypes of serum amyloid A protein (SAA), a sensitive acute phase reactant in patients with rheumatoid arthritis, rheumatoid arthritis with reactive amyloidosis and those undergoing surgery. The analysis was performed using FPLC system with Mono Q, ion exchange chromatocolumn, for the separation of low molecular fraction, which was obtained by the molecular sieve filtration. Four peaks, I-a, I-b, II and III were separated by FPLC analysis. Peaks II and III were the main isotypes of SAA and I-b was detected only in few cases. Although the recovery was low and varied after the filtration, the results obtained by FPLC were reproducible. Although peak I-a in RA with amyloidosis tended to be less than in other disorders, there was no specific patterns of SAA isotypes corresponding to each disorder.     

Reevaluation of optimum extraction condition for urinary organic acids using a stable isotope dilution technique]

We reevaluated the optimum conditions for analysis of 13 urinary organic acids using solvent extraction and GC/MS by the stable isotope dilution technique. The acids analyzed were uracil, and lactic, oxalic, 3-hydroxybutyric, succinic, fumaric, glutaric, adipic, pyroglutamic, 2-ketoglutaric, orotic, sebacic, and citric acids. Analytical recovery and accuracy for 13 organic acids ranged from 90 to 107% and from 1.6 to 13.7%, respectively. The optimal pH for most organic acids was 1-2, while that for oxalic and citric acids was 0.25, and that for 2-ketoglutaric and orotic acids was 0.5. The presence of urinary albumin decreased the extraction rates of organic acids, especially of orotic and citric acids; in slight albuminuria (0.5 g/l) the extraction recovery (the extraction rate with albumin/that without albumin) of orotic and citric acid was 38% and 67%, respectively, and in more marked albuminuria (5 g/l), 6% and 26%. Membrane pretreatment with Centricon-3 improved these extraction rates under the condition of albuminuria. Dehydration with the desiccant agent decreased urinary acid extraction rates, especially of uracil and orotic and citric acids. The extraction rates of these three organic acids was decreased in albuminuria and by the desiccant agent. Accurate quantitative analysis of urinary organic acids by the stable isotope dilution technique is necessary for routine examination conducted in clinical laboratories.     

Quantitative counterimmunoelectrophoresis for urinary fibrinogen-related antigens.

A quantitative procedure for urinary fibrinogen-related antigens, applying counterimmunoelectrophoresis to serial dilutions of concentrated samples against standards of known fibrinogen concentrations, is described. It is fast, convenient, sensitive enough (r = 0.8729, p less than 0.001), and can be easily incorporated into routine laboratory work.     

Quantitative analysis of amino acid oxidation and related gluconeogenesis in humans.

Significant gaps remain in our knowledge of the pathways of amino acid catabolism in humans. Further quantitative data describing amino acid metabolism in the kidney are especially needed as are further details concerning the pathways utilized for certain amino acids in liver. Sufficient data do exist to allow a broad picture of the overall process of amino acid oxidation to be developed along with approximate quantitative assessments of the role played by liver, muscle, kidney, and small intestine. Our analysis indicates that amino acids are the major fuel of liver, i.e., their oxidative conversion to glucose accounts for about one-half of the daily oxygen consumption of the liver, and no other fuel contributes nearly so importantly. The daily supply of amino acids provided in the diet cannot be totally oxidized to CO2 in the liver because such a process would provide far more ATP than the liver could utilize. Instead, most amino acids are oxidatively converted to glucose. This results in an overall ATP production during amino acid oxidation very nearly equal to the ATP required to convert amino acid carbon to glucose. Thus gluconeogenesis occurs without either a need for ATP from other fuels or an excessive ATP production that could limit the maximal rate of the process. The net effect of the oxidation of amino acids to glucose in the liver is to make nearly two-thirds of the total energy available from the oxidation of amino acids accessible to peripheral tissues, without necessitating that peripheral tissues synthesize the complex array of enzymes needed to support direct amino acid oxidation. As a balanced mixture of amino acids is oxidized in the liver, nearly all carbon from glucogenic amino acids flows into the mitochondrial aspartate pool and is actively transported out of the mitochondria via the aspartate-glutamate antiport linked to proton entry. In the cytoplasm the aspartate is converted to fumarate utilizing urea cycle enzymes; the fumarate flows via oxaloacetate to PEP and on to glucose. Thus carbon flow through the urea cycle is normally interlinked with gluconeogenic carbon flow because these metabolic pathways share a common step. Liver mitochondria experience a severe nonvolatile acid load during amino acid oxidation. It is suggested that this acid load is alleviated mainly by the respiratory chain proton pump in a form of uncoupled respiration.(ABSTRACT TRUNCATED AT 400 WORDS)     

Quantitative studies of urinary immunoglobulins in hospital patients including patients with urinary tract infection

The 24-hr urinary excretion and clearances of IgA, IgG, siderophilin and albumin have been determined on specimens from twenty-one hospital patients, nine of whom had urinary tract infection. Patients with normal creatinine clearance and urinary tract infection had significantly increased urinary excretion and clearances of all four proteins, compared to patients with normal creatinine clearance and no urinary tract infection. IgM was found in the urine of five patients with urinary tract infection, and in three of these IgD was also present. There was no evidence that the presence of IgM and IgD in the urine of these patients was a direct result of infection.     

2种疾病患者尿液有机酸代谢谱主成分的确定及分析

目的采用主成分分析法分析重症肌无力、线粒体肌病和健康者尿中22种有机酸代谢产物的特征,为临床筛查提供资料和依据。方法通过获得主成分及相应的主成分方程,解释主成分的理化意义。结果前5个主成分累积贡献率达到86.89%,被确定为主要成分;建立主成分函数表达式,分析主成分与原始变量之间的关系;发现苯基饱和酸类可能是2种疾病的潜在生物标志物成分;马尿酸为2种疾病预警成分。结论尿有机酸代谢谱主成分分析,有助于疾病的生物标志物的发现和为辅助临床诊断提供科学依据。     

Quantitative autoradiographic analysis of excitatory amino acid receptors in the cat spinal cord.

Using quantitative autoradiography, we have studied the density and distribution of N-methyl-D-aspartate (NMDA), kainate and AMPA receptors and the binding site for the sodium-dependent EAA transporter in sections from the cat spinal cord. NMDA, kainate and AMPA receptors were found in highest concentrations in laminae I and II of the dorsal horn. Lower levels of all receptors were seen in other regions of the spinal cord grey matter. The distribution of the sodium-dependent transporter was unlike that of any of the receptor populations with highest levels found in the ventral horn with slightly lower levels in other regions of grey matter. The pattern of binding sites was consistent throughout all levels of the spinal cord.     

Epithelial tumors of the urinary bladder]

Morphological, electron-microscopy, and histochemical investigations of the normal human mucous membrane of the bladder and 450 vocus epithelial tumours of the same localization were carried out, which made it possible to work out additional criteria for determining the degree of differentiation of tumourous cells. The structural-functional features of tumourous cells observed were used as histochemical and ultrastructural markers of the degree of maturity of different transitional-cell tumours and were taken into account in the course of the development of the pathoanatomic classification of epithelial tumours of the bladder in man.     

Quantitative analysis of islet glutamic acid decarboxylase p64 autoantibodies in insulin-dependent diabetes mellitus.

Autoantibodies against the beta-cell M(r) 64,000 protein (p64), recently identified as an isoform of glutamic acid decarboxylase (GAD), are prevalent in patients with insulin-dependent diabetes mellitus (IDDM). Dog islets were found to represent an abundant source of native p64 allowing the study of antigen-antibody interactions in IDDM. A quantitative, standardized assay for p64 antibodies based on dog islets was developed and evaluated. Utilizing dog and human islets the p64 antibodies were detected in 17/19 (89%) new onset 15-32-year-old patients, compared to 15/19 (79%) in a rat islet assay. ICA were detected in 15/19 (79%) patients and correlated with the presence of p64 antibodies (rs = 0.59, P < 0.004) but not with age at onset, sex, or C-peptide levels. Sensitivity therefore is improved with the dog islet p64 antibody assay which will allow future studies requiring native p64 antigen in larger quantities are possible based on our findings.     

Clinical assessment of urinary free L-fucose levels]

We measured urinary levels of free L-fucose in healthy subjects, patients with benign diseases, and patients with cancer using an automated analyzer and a newly isolated L-fucose dehydrogenase, and evaluated the clinical usefulness of the results. The values obtained were corrected for urinary creatinine as micromoles per gram of creatinine. The cutoff value, set at the mean + 2SD for the healthy subjects, was 250 mumol/g.Cr. Patients with gallbladder cancer, bile-duct cancer, liver cancer, pancreatic cancer, or cirrhosis of the liver had significantly higher levels of L-fucose than the healthy subjects. The diagnostic sensitivity for these five diseases, taken together, was 68% (144/213). Specificity for the detection of cancer was calculated by use of false positives for patients with cholelithiasis, hepatitis, and pancreatitis: it was 73% (76/104). Diagnostic accuracy for these seven diseases taken together was therefore 69% (220/317). We compared the positive ratio of the L-fucose level with that of the tumor markers AFD and CA19-9. The positive ratio of an L-fucose value above the cutoff was higher than the positive ratio of either marker in bile-duct cancer, gallbladder cancer, liver cancer, and pancreatic cancer. The results suggested that the urinary levels of free L-fucose reflected the metabolism of sugar chains of glycoconjugates, and may be usefully clinically as a tumor marker.