Evaluation of chemiluminescence method for the analysis of plasma homocysteine and comparison with HPLC method in children samples

Homocysteine concentrations in overweight children and adolescents

OBJECTIVE

The aim of this study was to describe homocysteine concentrations in overweight and obese children and adolescents and relate them to blood pressure levels, renal function, and insulin resistance.

METHODS

This is a cross-sectional and observational study with 64 overweight children and adolescents (mean age: 11.6±3.5 years) in outpatient follow-up. The following parameters were evaluated: body mass index z-score, waist-to-height circumference ratio, pubertal stage, blood pressure, serum homocysteine, glycemia, insulin, lipid profile, renal function, high-sensitivity C-reactive protein, microalbuminuria, and creatinuria. Statistical analysis: analysis of variance and logistic regression (dependent variable: homocysteine) (p<0.05).

RESULTS

The mean body mass index z-score was 2.9±1.1. The mean homocysteine concentrations were 8.6±2.2 μmol/L (10th and 90th percentiles: 6.6 and 11.2 μmol/L, respectively), with no difference when compared with children with severe obesity and obesity/overweight (p=0.431). High values of waist-to-height ratio (93.8%), systolic blood pressure (18.8%), diastolic blood pressure (12.5%), glycemia (4.7%), low-density lipoprotein cholesterol (31.1%), triglycerides (35.9%), non-high-density lipoprotein cholesterol (34.4%), and microalbuminuria (21.9%) were obtained. The mean glomerular filtration rate was 122.9±24.6 mL/min/1.73 m². Homocysteine concentrations were not associated with any of the studied variables (R²=0.095).

CONCLUSION

Homocysteine concentrations in overweight children and adolescents (mean 8.6±2.2 μmol/L) were not associated with body mass index z-score, blood pressure, renal function, and insulin resistance.

Low serum lycopene, and adequate α-tocopherol levels in patients with psoriasis: A cross-sectional study

BACKGROUND

Psoriasis is a chronic, immune-mediated skin disease. It affects skin and joints, characterized by abnormal hyperproliferation of keratinocytes. The worldwide prevalence of psoriasis ranges from 2% to 4%. Environmental factors as smoking, alcohol consumption obesity can also work as triggers. During the inflammatory process, there is an exacerbated formation of free radicals and antioxidants are required to maintain redox balance.

AIM

Assess antioxidant profiles.

METHODS

A cross-sectional study was conducted between August/2012 and March/2014. Sociodemographic, lifestyle, and biochemical measurements, dietary intake, serum lycopene and α-tocopherol, psoriasis severity according to Psoriasis Area and Severity Index were obtained. Comparisons between serum lycopene and α-tocopherol distributions according to variables were conducted using a one-way analysis of variance. Multiple linear regression was used to investigate factors associated with serum antioxidants.

RESULTS

81 participants (56% female, 62% non-white), 34% without psoriatic lesions, 51% diagnosed with mild psoriasis, and 15% with moderate psoriasis. Median (IQR) age of 54 (41, 62) years, 10 (4, 11) years of education, 17% smokers, 46% overweight and 25% obesity. In total, 72% did not reach the daily recommendation of fruit and vegetable intake. Serum lycopene and α-tocopherol were 0.2 (0.1-0.3) µmol/L and 22.5 (18.5-25.6) µmol/L, respectively. Only 14% presented adequate concentration of lycopene, but adequate α-tocopherol level was observed among 88%.

CONCLUSIONS

Patients reported a diet low in vegetables and fruits and rich in ultra-processed foods and fatty acids. Adequate circulating α-tocopherol but low serum lycopene, was observed among patients. A linear trend was observed for lycopene according to the severity of psoriasis.

Folate Nutritional Status among Psoriasis Patients not Exposed to Antifolate Drug

Background:

Folic acid fortification program has been established to prevent tube defects. However, concern has been raised among patients using anti-folate drug, i.e. psoriatic patients, a common, chronic, autoimmune inflammatory skin disease associated with obesity and smoking.

Objective:

To investigate dietary and circulating folate, vitamin B12 (B12) and homocysteine (hcy) in psoriatic subjects exposed to the national mandatory folic acid fortification program.

Methods:

Cross-sectional study using the Food Frequency Questionnaire, plasma folate, B12, hcy and psoriasis severity using the Psoriasis Area and Severity Index score. Median, interquartile ranges (IQRs) and linear regression models were conducted to investigate factors associated with plasma folate, B12 and hcy.

Results:

82 (73%) mild psoriasis, 18 (16%) moderate and 12 (11%) severe psoriasis. 58% female, 61% non-white, 31% former smokers, and 20% current smokers. Median (IQRs) were 51 (40, 60) years. Only 32% reached the Estimated Average Requirement of folate intake. Folate and B12 deficiencies were observed in 9% and 6% of the blood sample respectively, but hyperhomocysteinaemia in 21%. Severity of psoriasis was negatively correlated with folate and B12 concentrations. In a multiple linear regression model, folate intake contributed positively to 14% of serum folate, and negative predictors were psoriasis severity, smoking habits and saturated fatty acid explaining 29% of circulating folate.

Conclusion:

Only one third reached dietary intake of folate, but deficiencies of folate and B12 were low. Psoriasis severity was negatively correlated with circulating folate and B12. Stopping smoking and a folate rich diet may be important targets for managing psoriasis.

Serum NGAL and Cystatin C Comparison With Urinary Albumin-to-Creatinine Ratio and Inflammatory Biomarkers as Early Predictors of Renal Dysfunction in Patients With Type 2 Diabetes

Introduction

Diabetic nephropathy is associated with specific histological changes. Early detection of poor glomerular and tubular function can be achieved with biomarkers of diabetes. The aim of this study was to evaluate the accuracy of kidney dysfunction biomarkers in type 2 diabetes (T2D).

Methods

Patients with T2D were grouped according to their glycated hemoglobin level. Patients' urine and blood samples were taken to measure cystatin C (CysC), neutrophil gelatinase-associated lipocalin, beta-trace protein levels, and the first morning void albumin-to-creatinine ratio. Patients in the end stage of renal disease or receiving dialysis were not included. Receiver operating characteristic curves were generated, and the areas under the curve were compared with the performance of the biomarkers used to evaluate kidney dysfunction in T2D.

Results

Ninety patients with T2D were chosen. CysC was positively correlated with creatinine (P < 0.001), estimated glomerular filtration rate (P < 0.001), and urinary beta-trace protein (P = 0.01). The area under the curve was 0.635 for CysC, 0.621 for serum neutrophil gelatinase-associated lipocalin, and 0.660 for the albumin-to-creatinine ratio. A crude logistic regression model showed a positive association between serum CysC (P = 0.01) and serum neutrophil gelatinase-associated lipocalin (P < 0.001). A linear regression model showed a positive association between serum CysC, creatinine, and estimated glomerular filtration rate (P < 0.001) but did not show a positive association with glycated hemoglobin (P = 0.892).

Discussion

Neutrophil gelatinase-associated lipocalin and serum CysC were positively associated with the presence of renal dysfunction and had better performance on receiver operating characteristic analysis than the other markers evaluated in patients with T2D without kidney dysfunction.

Systemic chemotherapy interferes in homocysteine metabolism in breast cancer patients

BACKGROUND

Hyperhomocysteinemia in breast cancer (BC) patients can be a risk factor for thromboembolic events. This study aimed to evaluate homocysteine and its cofators (folic acid and vitamin B12) concentrations and platelet count at diagnosis of BC, 3 and 6 months after the beginning of chemotherapy treatment and to correlate them with clinical data.

METHODS

Thirty-five BC patients were included; blood samples were obtained by venipuncture. Plasmatic Hcy and cofactors concentrations were measured by competitive chemiluminescent enzyme immunoassay method. Platelet count was done using an automated analyzer. Statistical analysis was performed using the software SPSS.

RESULTS

During chemotherapy, homocysteine (P = 0.032) and vitamin B12 (P < 0.001) concentrations increased, while folate and platelets decreased (P < 0.001). Among the clinical data, the menopausal status showed significant positive correlation (P = 0.022) with homocysteine concentration increase.

CONCLUSIONS

Evaluation of homocysteine concentrations during chemotherapy is extremely important because their levels increase during chemotherapy treatment, thus increasing the risk of thromboembolism development.