Establishment of age- and -gender specific reference intervals for amino acids and acylcarnitines by tandem mass spectrometry in Turkish paediatric population.

Introduction: We determined age- and gender-specific reference intervals (RIs) for acylcarnitines and amino acids by tandem mass spectrometry (MS/MS) in the Turkish paediatric population by using laboratory information system (LIS) data. Materials and methods: A total of 9156 MS/MS results of children between 0-18 years of age, were downloaded from the LIS. Premature infants and newborns followed in the intensive care unit were excluded and only the first result of each patient attending outpatient clinics was included. Children with a known or suspected diagnosis of metabolic disease, malignancy, epilepsy, mental retardation, or genetic disorder were excluded. Laboratory results were evaluated and children with any pathological laboratory finding were excluded, resulting in a final sample size of 3357 (2029 boys and 1328 girls). Blood was collected by capillary puncture and spotted on Whatman 903 filter paper cards and analysed by MS/MS (Shimadzu LCMS-8050, Shimadzu Corporation, Kyoto, Japan). Data were evaluated for age and gender differences and age partitioning was performed according to the literature and visual evaluation of the data. Age subgroups were: ≤ 1 month, 2 months-1 year, 2-5 years, 6-10 years, and 11-18 years. Results: There were significant age-related differences for the majority of amino acids and acylcarnitines thus age dependent RIs were established. Gender-specific RIs were established for tyrosine, leucine-isoleucine, isovalerylcarnitine (C5) and hexadecanoylcarnitine (C16). Conclusions: Establishing age-related RIs can enhance the quality of medical care by facilitating early diagnosis and therapy, especially in certain metabolic disorders presenting with mild biochemical abnormalities and subtle clinical manifestations.

The Evaluation of Intestinal Permeability in Preeclamptic Pregnancy.

Background: Zonulin is a physiological protein that regulates the tight connections and permeability of the intestine, serving as a biomarker for impaired intestinal permeability. Objective: The aim of this study was to examine zonulin levels in preeclampsia, to investigate its associations with the cellular immune response marker soluble interleukin-2 receptor (sIL-2R) and exogenous antigen load marker lipopolysaccharide binding protein (LBP) and to evaluate the implications of these findings in the etiopathogenesis of preeclampsia. Methods: We designed a cross-sectional case-control study and enrolled 22 pregnant women with preeclampsia and 22 healthy pregnant controls. Plasma zonulin levels were determined by ELISA. Serum sIL-2R and LBP levels were assessed by chemiluminescent immunometric methods. Results: Women with preeclampsia had lower levels of plasma zonulin and serum LBP than normotensive healthy controls (p<0,05). The difference in serum sIL-2R levels was not significant (p: 0,751). There was a negative correlation between plasma zonulin and serum urea (r: -0.319, p: 0.035) and a positive correlation between serum sIL-2R and ALT (r: 0,335, p: 0,026) and AST (r: 0,319, p: 0,035). Conclusion: We found that zonulin and LBP, but not sIL-2R, levels were significantly lower in pregnant women with preeclampsia as compared with healthy pregnant controls. Reduced intestinal permeability in preeclampsia might be associated with impaired immune system functions or a lower fat mass and malnutrition. Further studies are needed to elucidate the exact pathogenetic role of intestinal permeability in preeclampsia.

Obesity effects on sleep quality with anthropometric and metabolic changes.

OBJECTIVE: Obesity is one of the etiological factors of sleep disorders (e.g., obstructive sleep apnea and restless leg syndrome). The aim of this study was to determine the effect of obesity on sleep quality by using the Pittsburgh Quality Index and Berlin Question are and evaluate the association of sleep with anthropometric and metabolic parameters. METHODS: A total of 76 patients (41 females and 35 males) between the ages of 18 and 70 years with a body mass index >30 kg/m2 were included in this study. Homeostatic model assessment-insulin resistance, hemoglobin A1c, alanine aminotransferase, aspartate transaminase, total cholesterol, low-density lipoprotein, triglyceride, high-density lipoprotein, and thyroid-stimulating hormone levels were analyzed. Sleep quality was evaluated with the Pittsburgh Sleep Quality Index, Berlin Questionnaire, and the Restless Leg Syndrome Questionnaire. RESULTS: A significant correlation was observed between Pittsburgh sleep quality index and body mass index, neck circumference, body fat index, muscle mass, hip and waist circumference, hemoglobin A1c, and homeostatic model assessment-insulin resistance (ps<0.005). The Pittsburgh sleep quality index median (2.5-97.5 percentile) value was 8 (2-18.6) in the patient group and 3.5 (0.1-7.9) in the control group (p<0.0001). Body mass index was found to be the predictor on Pittsburgh sleep quality index (R2=0.162, F=3.726, analysis of variance p=0.008). Notably, 88% (67) and 95% (57) of the poor sleepers were found to be at high risk for obstructive sleep apnea according to Berlin Questionnaire and Pittsburgh Sleep Quality Index, respectively. Also, the frequency of restless leg syndrome was 45% in obese individuals. CONCLUSIONS: We observed a significant correlation between Pittsburgh sleep quality index and the anthropometric and metabolic parameters. Also, the frequency of obstructive sleep apnea and restless leg syndrome was 88% and 45%, respectively, in obese individuals.

Effect of ejaculation on Serum Prostate-Specific Antigen concentration.

PURPOSE: To evaluate the effect of ejaculation on serum prostate-specific antigen (PSA) concentrations in patients with lower urinary tract symptom (LUTS). MATERIALS AND METHODS: Our study includes 98 men (62 study and 36 control). After three days of sexual abstinence, blood samples were drawn for the measurement of baseline PSA levels. Then the patients were told to ejaculate. One, 5, 24 and 72 hours after ejaculation, serum total (tPSA), free (fPSA) and complexed PSA (cPSA) levels were measured. Serum PSA sampling was performed at the same intervals in the control group without ejaculation. RESULTS: The mean age in study and control groups patients were 59.03±0.99 years, 61.14±1.30 years, respectively. In the study group, changes in tPSA and fPSA levels after ejaculation were found statistically significant while changes in cPSA levels and f/tPSA ratios were not significant (p=0.016, p=0.0003, p=0.176, and p=0.173, respectively). Baseline values showed significant differences with 1st and 5th hours. No significant changes in tPSA, fPSA, cPSA levels and f/tPSA values were found in control group (p=0.223, p=0.224, p=0.444, and p=0.718, respectively). The changes in the number of patients exceeding the cutoff values after ejaculation were not statistically significant for tPSA, cPSA, and f/tPSA ratio. CONCLUSIONS: In this study, ejaculation increased tPSA and fPSA concentrations but it didn't have a significant effect on serum cPSA levels and f/tPSA ratios. However, recent ejaculation may affect the biopsy indication at least near cut off PSA values. Further studies are needed to explain the mechanisms of alterations in the concentration of PSA.

The effectiveness of BD Vacutainer® Plus Urinalysis Preservative Tubes in preservation of urine for chemical strip analysis and particle counting.

INTRODUCTION: The aim of this study was to evaluate the stability of urine collected in preservative tubes for chemistry strip analyses and particle counting to determine whether the transport of urine samples with all of their constituents is possible. MATERIALS AND METHODS: 275 pathologic urine specimens were included. Each urine sample was evaluated after 4, 8, 12, 24, and 48 hours of storage in BD Vacutainer(®) Plus Urinalysis Preservative (BD UAP) tubes and compared with refrigeration at 4 °C. All analyses were peformed on H-800 and FUS-200 automatic modular urine analyzers (Dirui Industry, Changchun, China). The kappa coefficients (κ), false positive (FP) and false negative (FN) rates were evaluated. κ > 0.8 was accepted as good agreement. RESULTS: Haemoglobin (Hb), leucocyte esterase (LE), and protein (Pro) analyses should be performed within 4 hours, whereas glucose (Glc) was stable until the end of 48 hours in both storage conditions. Nitrite (Nit) was well preserved in BD UAP tubes for 24 hours but was stable only up to 8 hours at 4 °C. Bilirubin (Bil) had very high FN rates even at 4 hours in both conditions. The particle counting showed high FN rates for white blood cells (WBC) and red blood cells (RBC), whereas squamous epithelial cells (EC) were stable up to 8 hours in both conditions. CONCLUSIONS: Preanalytical requirements for both urine chemical strip analyses and particle counting in a unique sample were not met in either condition. Thus, the transfer of urine samples for centralization of urinalysis is not yet feasible.

A Comparison of Three Widely Used Immunoassay Systems in Cortisol Measurement.

BACKGROUND: Interassay variability is one of the challenging issues of routine clinical laboratory practice. Commercial plasma cortisol immunoassays are also subject to this issue. In this study, we intended to evaluate the interchangeability of cortisol results of three widely used immunoassay systems. METHODS: The cortisol values of 150 serum samples measured by three immunoassay systems, Beckman Coulter DXI 800, Roche Modular E170, and Siemens Immulite 2500, were compared. RESULTS: A degree of proportional biases was observed between all three methods; DXI 800 showed the worst biases with the other two systems (slope values 0.67 and 0.77 with E170 and Immulite 2500, respectively). DXI 800 showed poor agreement with other methods (CCC: 0.83 and 0.87, respectively). There was a moderate agreement between E170 and Immulite 2500 (CCC: 0.92). CONCLUSIONS: All three methods showed a degree of variability among themselves. DXI 800 results were not interchangeable with the other two systems.

Serum thymidine kinase 1 levels correlates with FDG uptake and prognosis in patients with non small cell lung cancer.

CONTEXT: TK1 found to be elevated biomarker in many solid cancers. OBJECTIVES: The study aimed to assess the prognostic significance of a serum TK1 in patients with metastatic NSCLC. METHODS: The study included 48 consecutive patients, newly diagnosed with metastatic NSCLC, and 10 healthy volunteers. Serum TK1 activity determined by ELISA method. RESULTS: Patients with a bTK1 level >156 Du L(-1) had significantly shorter survival. TK1 level showed a strong correlation with primary tumor SUV(max). DISCUSSION AND CONCLUSION: The magnitude of maximum fluorodeoxyglucose uptake in primary tumors and the serum TK1 level in patients with metastatic NSCLC were found to be independent prognostic predictors of overall survival.

Netrin-1 concentrations in patients with advanced gastric cancer and its relation with treatment.

CONTEXT: Netrin-1 is found to be elevated and usable as a diagnostic biomarker in many human cancers. OBJECTIVES: We evaluated serum Netrin-1 concentrations in patients with advanced gastric cancer compared with those in a healthy group. MATERIAL AND METHODS: Thirty patients with advanced gastric cancer and thirty healthy people were included in the study. Serum netrin-1 concentrations were measured by quantitative ELISA method in both groups. RESULTS: The mean serum Netrin-1 concentrations were found to be significantly higher in patients with gastric cancer than in healthy controls. The mean serum Netrin-1 concentrations were found to be significantly higher in patients with gastric cancer before the beginning of chemotherapy when compared after the completion of third cycle. DISCUSSION AND CONCLUSION: Our results indicated that netrin-1 concentrations elevated in advanced gastric cancer compared to a healthy control group and netrin-1 concentrations decreased with chemotherapy.