Serum sialic acid in normals and in cancer patients

A simple procedure is described for the detection of sialic acid in serum. After a direct addition of Ehrlich reagent to serum and an incubation at 56 degrees C for eight hours, the resulting mixture is diluted with saline. After centrifugation, the color in the supernatant is determined at 525 nm in a spectrophotometer. Serum sialic acid was significantly greater in cancer patients than in normals. Cancer patients with metastases had significantly greater sialic acid than cancer patients without metastases. In two cancer patients, sialic acid levels returned to normal after surgery. The diagnostic usefulness of 95.6% was similar to that reported with lipid-soluble sialic acid and seemed to be superior to CEA and other tumor antigens associated with a limited spectrum of tumors. However, patients with inflammatory diseases such as arthritis, Crohn's disease and psoriasis also showed elevated sialic acid levels. Ultrafiltration showed that almost all of the sialic acid was retained on an Amicon filter, which suggests that sialic acid was bound to a macromolecule. A quality control serum run 25 times had a coefficient of variation (CV) of 8.4% and the same serum ran on 42 days had a CV of 11.6%.     

Serum total sialic acid in cholangiocarcinoma patients: an ROC curve analysis.

OBJECTIVES: This study was undertaken to establish the diagnostic utility of serum total sialic acid (TSA) for patients with cholangiocarcinoma (CCA). DESIGN AND METHODS: Serum TSA was determined in 89 histologically confirmed CCA patients, 38 with benign hepatobiliary diseases (BHD) and 43 healthy persons. To check whether the test could adequately discriminate between these groups, complete statistical Receiver Operating Characteristic (ROC) curves were analyzed. RESULTS: The mean value of serum TSA in CCA patients (2.75 +/- 0.67 mmol/L) was significantly higher than that in the BHD (2.33 +/- 0.69 mmol/L p < 0.002) and healthy persons (1.89 +/- 0.46 mmol/L p < 0.001) groups. The areas under the ROC curves were 0.6699 and 0.8558, respectively. A cut-off value of 2.33 mmol/L discriminated between the CCA, BHD and healthy groups with a sensitivity of 71.9% and a positive predictive value range of 80 to 89%. CONCLUSION: Determination of TSA yielded high diagnostic values for differentiating between CCA, BHD and healthy persons. The determination of serum TSA would be most useful as an adjunct diagnosis rather than an early detection and screening tool because of the apparent nonspecificity of SA to a given disease.     

The relationship of serum total sialic acid with serum acute phase proteins and lipoprotein (a) in patients with severe hypertriglyceridaemia

Abstract. Total serum sialic acid (TSA), recently shown to be a cardiovascular risk factor, was measured in 15 patients with severe hypertriglyceridaemia (fasting triglyceride > 2·3 mmol l^-1) and 15 age and sex matched normal control subjects.
To test the hypothesis that serum TSA is related in some way to serum acute phase proteins we also measured five acute phase proteins, namely alpha-1-antichymotrypsin (ACT), alpha-1-acid-glycoprotein (AGP), alpha-2-macroglobulin (AMG), C-reactive protein (CRP) and haptoglobin (HAP) in both groups.
Of note was the significantly elevated serum TSA in the severely hypertriglyceridaemic group as compared to normal subjects. Serum TSA being 71·9 ± 11·7 mg dl^-1 and 59·6 ± 10·2 mg dl^-1 respectively ( P < 0·01 Mann-Whitney test).
Serum CRP was significantly elevated in the type IV patients as compared to controls (6·4 ± 4·5 mg l^-1 vs. 3·3 ± 1·9 mg l^-1 P <0·05 Mann Whitney test) as was serum AMG (2·1 ± 0·89 g l^-1 vs. 1·5 ± 0·53 g l^-1 P < 0·05 Mann Whitney test).
There was no correlation between serum TSA and lipoprotein (a) in either the normal or severely hypertriglyceridaemic subjects. We suggest that serum TSA could in part be related to hypertriglyceridaemia and serum acute phase proteins but that its property as a cardiovascular risk factor is not related to serum lipoprotein (a) concentrations.     

Serum sialic acid in a random sample of the general population.

BACKGROUND: The serum sialic acid (SA) concentration has been reported to be a potentially useful but nonspecific disease marker. We wanted to study which factors influence SA concentration in a well-characterized healthy population. METHODS: SA was determined in 97 women and 96 men with a colorimetric Warren method. RESULTS: The mean +/- SD concentrations of SA were 634 +/- 109 (95% confidence interval, 612-656) and 630 +/- 106 (95% confidence interval, 608-651) mg/L for women and men, respectively. The serum SA showed a significant positive association with body mass index and with systolic and diastolic blood pressure among both women and men. SA also correlated significantly with the use of contraceptive pills and age among women and with smoking among men. CONCLUSIONS: Our study suggests that SA does not increase with age in men but appears to increase with female menopause. The strong positive association with blood pressure may explain why SA predicts cardiovascular mortality.     

Serum sialic acid changes in type 2 diabetic patients on metformin or rosiglitazone treatment

What is known and objective: Serum sialic acid is a recently investigated potential risk‐marker for cardiovascular complications. There is a known association between sialic acid and cardiovascular complications in diabetes mellitus. We aimed to investigate the effect of antidiabetic drugs on the serum concentration of sialic acid. Methods: We investigated the effect of metformin and rosiglitazone on the concentration of sialic acid in 120 type 2 diabetic patients, divided into a group (n = 60) receiving metformin and a group (n = 60) receiving rosiglitazone treatment. Results: Serum sialic acid was significantly higher in patients on rosiglitazone (66·90 ±8·80 mg/dL vs. 57·6 ± 8·46 mg/dL, P <0·01) and metformin (61·95 ± 10·49 mg/dL vs. 57·6 ±8·46mg/dL, P < 0·04) when compared with control subjects. In addition, rosiglitazone‐treated patients showed a significant increase in cardiovascular risk factors, notably total cholesterol (246·45 ± 20·2 mg/dL vs. 170·6 ± 15·1 mg/dL, P =0·01), triglyceride (178 ± 9·20 mg/dL vs. 149·35 ±6·31 mg/dL, P < 0·04) and glycohemoglobin (HbA1‐c) concentration (8·17 ± 1·43% vs. 4·38 ±0·96%, P < 0·02) compared with normal control subjects. The patients on metformin also showed significantly higher levels of serum glucose (133·7 ± 9·63 mg/dL vs. 88·35 ± 6·31 mg/dL, P <0·04) and glycohemoglobin (HbA1‐c) (8·23 ±1·75% vs. 4·38 ± 0·96%, P < 0·02) when compared with control subjects. Comparison of the two groups of patients revealed a significantly higher serum sialic acid (66·90 ± 8·80 mg/dL vs. 61·95 ±10·49 mg/dL, P < 0·05), total cholesterol (246·45 ±20·2 mg/dL vs. 192 ± 14·23 mg/dL, P <0·02) and triglyceride (178 ± 9·20 mg/dL vs. 158 ± 14·51mg/dL, P < 0·05) concentrations in the rosiglitazone‐treated patients. What is new and conclusions: This study suggests significantly higher levels of serum sialic acid and other cardiovascular risk factors in rosiglitazone‐treated patients than in metformin‐treated patients. The lower sialic acid concentration may explain a better metformin antidiabetic effect than with rosiglitazone.     

Serum concentration of uric acid, a diagnostic 'must' in patients with hyponatremia

The renal handling of urate involves complete glomerular filtration followed by reabsorption and secretion mainly in the proximal renal tubule. The amount of urate excreted depends on the extracellular fluid volume. Expansion of extracellular fluid volume increases and contraction of extracellular fluid volume decreases the clearance of urate. In the syndrome of inappropriate secretion of antidiuretic hormone, there is volume expansion associated with low uric acid. A comparable situation is observed whenever exaggerated amounts of free water are consumed. Similarly, hypouricaemia and a tendency to low serum sodium concentrations are observed in normal pregnancy, a state with volume expansion, a physiological situation reversed when eclampsia occurs. On the other hand, when hyponatraemia is associated with contraction of extracellular fluid volume as it is often the case when thiazides or loop-diuretics are administered, hyponatraemia is paralleled by increased serum uric acid concentrations.     

Serum total and lipid-bound sialic acid levels following acute myocardial infarction.

Although serum total sialic acid has been shown to be a cardiovascular risk factor, with elevated levels associated with increased cardiovascular mortality and also with cerebrovascular disease, the reason for the elevation in serum sialic acid content remains obscure. It has been shown that an increased output of serum proteins by the liver due to some type of acute phase reaction may be one of the possible sources of an increased serum sialic acid concentration in patients with myocardial infarction. An increase in the activity of sialidase, which cleaves the terminal sialic acid residues from oligosaccharides, glycoproteins and gangliosides, may also play an important role in the elevation of serum total sialic acid in myocardial infarction. Elevated serum total sialic acid in the blood might result either from the shedding or secreting of sialic acid from the cell membrane surface, or releasing of cellular sialic acid from the cell into the bloodstream due to cell damage after myocardial infarction. The purpose of the present study is to investigate serum total and lipid-bound sialic acid and the enzymes serum lactate dehydrogenase, creatine kinase and aspartate aminotransferase in patients with acute myocardial infarction, at 24 h post-infarction (day 1), 48 h post-infarction (day 2) and 72 h post-infarction (day 3). A possible role of cell damage in the elevation of serum total and lipid-bound sialic acid levels in these patients was also evaluated. In this study, 40 patients with myocardial infarction ranging in age from 42 to 68 years, and 26 healthy volunteers ranging in age from 45 to 71 years were included. Serum total sialic acid determination was carried out by the thiobarbituric acid method of Warren and lipid-bound sialic acfd by the method of Katopodis. Our data shows that a) there is a gradual increase in the levels of serum total sialic acid and lipid-bound sialic acid during the first three days after the acute myocardial infarction and b) the elevation in serum total sialic acid levels correlates with the elevation in lactate dehydrogenase activity only on day 1 following infarction. Therefore, either the shedding or secreting of sialic acid from the cell or cell membrane surface may be partly responsible for an increased serum sialic acid concentration especially on day 1 following myocardial infarction.     

Serum concentrations of lipid bound sialic acid and acute phase proteins in patients with cancer and nonmalignant disease

Levels of serum lipid bound sialic acid (LSA) were determined in lung cancer and the inflammatory reaction associated with pneumonia, rheumatoid arthritis and surgical wounding. The mean levels of serum LSA were raised in all these disorders and levels were closely correlated with serum alpha 1-acid glycoprotein (AGP) r = 0.9. Levels of AGP and LSA rose and fell in parallel following cholecystectomy. The major influence on the concentration of serum lipid bound sialic acid is the intensity of the response to inflammation.     

原发性高血压患者血清脂联素水平的研究

目的:探讨原发性高血压患者血清脂联素水平及其与血压之间的关系.方法:选取原发性高血压患者50例及健康对照者30例,用酶联免疫吸附法检测各组空腹血清脂联素浓度,同时测定各组的血压、体质指数、血糖、血脂及胰岛素等指标,采用稳态模型法计算胰岛素抵抗指数,并分析各指标间的相关性.结果:原发性高血压组血清脂联素水平显著低于正常对照组[(7.70±2.03)mg/L vs(10.83±2.58)mg/L,P＜0.01];原发性高血压组血清脂联素水平与收缩压、舒张压、平均压之间存在显著负相关;多元回归分析显示,收缩压与舒张压是影响脂联素水平的独立危险因素.结论:在原发性高血压患者中,脂联素水平下降并与血压之间存在一定的相关性.     

Secondary hypertriglyceridaemia in patients with parenchymal liver disease

Hypertriglyceridaemia occurring in patients with liver disease has been studied by measuring hepatic triglyceride lipase (H-TGL) and plasma lipoprotein lipase (LPL) by selective precipitation of H-TGL with specific antibodies. Lipid analysis, determination of lecithin-cholesterol-acyltransferase (LCAT) activity, and liver function tests were performed in parallel in fifty patients with acute hepatitis, twenty patients with chronic active or persistent hepatitis and fifty with cirrhosis of the liver. Total post-heparin lipolytic activity (PHLA) decreased with the severity of liver dysfunction. This decrease was due to low H-TGL and only to some degree to low LPL activity. With improvement over several weeks of hospitalization, hypertriglyceridaemia disappeared with a concomitant increase of H-TGL and LPL. It is concluded that impaired triglyceride metabolism in liver disease is at least partly caused by diminished plasma hepatic TGL activity.     

Serum concentration and phototoxic effect of methoxsalen in patients with psoriasis.

The correlation between serum concentration of methoxsalen (8-methoxypsoralen; 8-MOP) and phototoxic effect using long-wave ultraviolet light has been studied in 5 psoriatic patients. The maximum serum concentration occurred between 0.5 and 2 hr after oral administration of 0.6 mg/kg of methoxsalen. The lowest value for the minimum phototoxic dose (MPD), i.e., highest photosensitivity, was obtained between 1 and 2 hr. There was a significant negative correlation between the logarithm of the serum concentration and minimum phototoxic dose (MPD) (r = 0.780). Hence, the degree of photosensitivity appears to be related to the serum level of methoxsalen.     

Serum concentration of 5-S-cysteinyldopa in patients with melanoma

BACKGROUND: 5-S-cysteinyldopa (5-S-DC) is a precursor of melanin. Its serum and urinary level can reflect melanoma progression. In this study we examined the concentration changes of 5-S-CD in melanomas of different clinical stages and in patients with different symptoms of melanoma, during and after treatment. METHOD: Serum samples were taken from 252 melanoma patients on 765 occasions, from June 1996 to July 1998. Levels of 5-S-CD were determined by HPLC. RESULTS: The value of 5-S-CD in patients with primary melanoma and in patients without symptoms ranged around the normal level. There was a significant difference between the values of patients with or without symptoms. There was also a significant difference between the 5-S-CD values at clinical Stage I and Stage III, as well as at clinical Stage II and Stage III, respectively. Analysing the values of patients with symptoms we found a significant difference between the mean values of primary tumour and stage III, between values in lymph node metastasis and stage III, between values in lung metastasis and stage III. The tumour burden was found to correlate with a rising marker level. In 7% of the symptomatic patients that had a marker level under the upper limit, amelanotic primary tumour was detected. CONCLUSION: According to the high marker level in lung and liver metastases, the marker might be useful in monitoring both patients with disease free ocular melanomas, to detect liver metastasis and high-risk patients after surgical removal of the primary tumour to reveal lung metastases.     

Plasma protein-bound sialic acid in patients with colorectal polyps of known histology

Protein-bound sialic acid (PBSA) was measured in serial plasma specimens from 62 healthy subjects, 48 patients with colorectal polyps, and 30 patients with colorectal adenocarcinomas. The mean plasma PBSA concentration in healthy smokers was significantly greater than that in healthy nonsmokers and healthy ex-smokers (P less than 0.0001). Villoglandular polyps were associated with higher plasma PBSA values than were the most benign hyperplastic polyps (P less than 0.025). Patients with the most neoplastic villoglandular and villous polyps had significantly greater (P less than 0.010-0.050) plasma PBSA values than healthy subjects. Polypectomy decreased the mean PBSA value significantly to the mean value for healthy subjects only for patients with villoglandular (P less than 0.010) or villous (P less than 0.050) polyps. Colorectal cancer patients had mean plasma PBSA concentrations significantly greater than those for the healthy subjects (P much less than 0.001) and the polyp patients (P much less than 0.001). Surgery significantly reduced (P less than 0.025) the mean PBSA value for the cancer patients to the mean PBSA value observed for the healthy subjects.     

冠心病患者血清胆红素浓度分析

目的　探讨血清总胆红素浓度与冠心病的关系。方法　将 2 31例行冠状动脉造影的患者分成两组 ,主要冠状动脉中任何一支内径减少≥ 5 0 %者为冠心病组 ,共 135例。冠状动脉造影正常者为对照组 ,共 96例。两组均采清晨空腹静脉血测定血清总胆红素浓度 ,探讨冠心病与胆红素水平的关系。结果　冠心病患者血清总胆红素浓度明显低于非冠心病组 (P <0 .0 5 ) ,血清总胆红素与总胆固醇、低密度脂蛋白胆固醇、载脂蛋白B水平呈负相关。结论　低胆红素血症可能是冠心病危险因子之一 ,胆红素对血脂代谢有影响     

Serum butyrylcholinesterase activity and phenotype associations with lipid profile in stroke patients

Background

Butyrylcholinesterase (BuChE) catalyzes the hydrolysis of acetylcholine and other choline esters and is also involved in lipid metabolism. The purpose of this study was to investigate any association between BuChE serum phenotype and activity and lipid profile of ischemic stroke patients.

Methods

We determined serum BuChE activities and phenotypes, and levels of total cholesterol (TC), LDL-C, HDL-C and triacylglyerol (TG) in 33 patients with acute ischemic stroke within 12 h of the onset of the attack and 29 controls.

Results

The mean (± SD) serum BuChE activity and the BuChE of U/A phenotype in the stroke individuals were significantly lower and higher than that of the control (315 (± 124) IU/L. vs. 384 (± 99) IU/L, p = 0.02, t = − 2.4 and 21.2% vs.3.4%, p = 0.026 respectively).

Conclusions

Our results showed that a negative correlation between BuChE activity with TC level, in addition the frequency of BuChE phenotypes with low activity is high in stroke patients, who have high levels of cholesterol, may have increased susceptibility to stroke.     

Heparin-released lipolytic activity in the forearm vascular bed in patients with hypertriglyceridaemia

Summary. Hypertriglyceridaemia (HTG) may be caused by increased production or decreased removal of very low density lipoproteins (VLDL) or by a combination of these mechanisms. A decreased lipoproteinlipase activity (LLA) in the vascular wall of the tissues could be the mechanism of impaired removal. Therefore, the release of lipase activity from the forearm musculature after regional arterial injection of heparin was studied in healthy volunteers and patients with HTG. Heparin was injected in the doses 1·5, 15 and 150 i.u. and arterial and deep venous blood was sampled simultaneously at short intervals and analysed for LLA using intralipid with triple ¹⁴C-oleate as substrate. There was no significant difference in release of lipolytic activity between the groups and there was no significant correlation between plasma triglyceride concentration and LLA release in the HTG group or the whole material. Thus, deficient skeletal muscle LLA does not seem to be a general causative mechanism in HTG.     

酶法检测唾液酸在肿瘤患者中的诊断效果

目的探讨酶法检测唾液酸在肿瘤患者中的诊断效果。方法选取2012年6月-2013年5月我院体检中心的50例健康者（正常对照组）、68例良性疾病患者（良性对照组）以及102例恶性肿瘤患者（恶性肿瘤组）,对各组患者治疗前唾液酸水平进行检测,并比较唾液酸在不同肿瘤病理类型以及治疗前后的水平变化。结果恶性肿瘤组患者其血清SA水平则较正常对照组、良性疾病组明显升高,其中肺癌、胃癌、直肠癌患者以及临床分期为Ⅲ期、Ⅳ期肿瘤患者相比正常对照组、良性疾病组患者升高明显（P〈0.05）。经治疗后好转组患者血清SA水平较未好转组患者明显降低（P〈0.05）,且好转组患者治疗后血清SA水平较治疗前明显下降（P〈0.05）,其中62例患者与病情相符,符合率为84.9%;而未好转组患者治疗前后血清SA水平并无明显差异（P〉0.05）,其中有23例患者与病情相符,符合率为79.3%;,差异具有统计学意义。结论酶法检测唾液酸对临床诊断肺癌、胃癌、直肠癌以及Ⅲ期、Ⅳ期肿瘤具有较好的诊断效果,也可作为判断患者治疗效果的辅助指标。     

Abnormal sialic acid content of the dysfibrinogenemia associated with liver disease.

To evaluate the possibility that the carbohydrate composition of fibrinogen may be altered in the dysfibrinogenemia associated with liver disease, we studied the sialic acid content of purified fibrinogen from 12 patients with liver disease and its relationship to the prolongation of the thrombin time. Purified fibrinogen showed that Aalpha-, Bbeta-, and gamma-chains when reduced and analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and exhibited prolongation of the thrombin time similar to that of the plasma from which it was derived. Sialic acid content of the purified fibrinogen ranged from 12.7 to 71.4% higher in patient fibrinogens when compared to normal controls. A progressive delay in thrombin time was associated with increasing sialic acid content of the patient fibrinogen. Enzymatic removal of sialic acid from four of the abnormal fibrinogens resulted in a shortening of their thrombin times to the range of the desialylated normal control. Periodic acid-Schiff reagent stained only the Bbeta- and gamma-chains of the reduced patient fibrinogens after sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggesting that the excess sialic acid is located on these two chains. These studies demonstrate a biochemical alteration of the functionally abnormal fibrinogen found in some patients with liver disease, and indicate that the excess sialic acid plays an important role in the functional defect of this protein.     

Total-and lipid-associated sialic acid in serum and thrombocytes in patients with chronic heart failure

ObjectivesTo investigate and discuss the total-, lipid-associated, and thrombocyte-sialic acid levels in chronic heart failure (CHF) patients.Design and methodsThirty-one chronic heart failure patients and 38 healthy controls were included in the study. Serum total sialic acid (TSA), lipid associated sialic acid (LASA), thrombocyte sialic acid (TrSA) were determined together with the traditional inflammation and prognostic markers.ResultsSerum TSA levels were significantly higher in patient group (3.08 ± 0.33 mmol/L) than control group (2.60 ± 0.17 mmol/L). Serum LASA, homocysteine, high-sensitivity CRP, brain natriuretic peptide and erythrocyte sedimentation rate were also significantly higher in patient group. TrSA levels were not significant between the groups.ConclusionTSA and LASA levels increase in CHF, independent from coronary artery disease. TrSA levels were not found to be a prognostic or valuable marker for CHF patients. Acute phase response and lipid associated portions of SA are thought to be responsible for SA rise in CHF.