INTRODUCTION: Homocysteine, an atherosclerotic marker, is thought to be associated with chronic inflammation and autoimmunity. The aim of this study was to investigate the association between the homocysteine level, lipid parameters, high-sensitivity C-reactive protein (hs-CRP), and autoantibodies in subclinical hypothyroid patients.
METHODS: A total of 100 cases, 50 patients who were older than 18 years of age and diagnosed with subclinical hypothyroidism due to Hashimoto’s thyroiditis and 50 controls with no known disease, were included in the study.
RESULTS: Homocysteine (9.6 µmol/L vs 5.5 µmol/L; p<0.001), hs-CRP (2.4 mg/L vs 0.9 mg/L; p<0.001), and low-density lipoprotein-cholesterol levels (115.9±32.7 mg/dL vs 100.3±23.9 mg/dL) (p=0.008) were determined to be higher in the subclinical hypothyroidism group, and the high-density lipoprotein (HDL) cholesterol level (51.2±12.7 mg/dL vs 58.8±15.2 mg/dL; p=0.008) was lower in the subclinical hypothyroidism group compared with the healthy control group. A positive correlation was determined between the homocysteine level and the hs-CRP (r=0.312; p=0.027), anti-thyroid peroxidase (r=0.505; p<0.001), and anti-thyroglobulin (r=0.318; p=0.031) levels in the subclinical hypothyroidism group.
DISCUSSION AND CONCLUSION: In the regression analysis performed, HDL cholesterol, hs-CRP, and homocysteine levels were each found to be an independent risk factor for subclinical hypothyroidism. Our results indicated that homocysteine was associated with subclinical hypothyroidism.

INTRODUCTION: There is growing evidence that oxidative modification of low-density lipoprotein (LDL) plays a central role in the pathogenesis of atherosclerosis, which is increasingly seen at younger ages, and that high-density lipoprotein (HDL) levels are inversely associated with the risk of coronary artery disease (CAD). Cholesteryl ester transfer protein (CETP) has a role in the regulation of plasma HDL levels. The most studied polymorphism in the CETP gene is the Taq1B polymorphism, which has consistently been correlated with HDL levels. This case control study of a young (<50 years) Turkish population group with CAD was designed to assess whether there is a relationship between LDL oxidation and CETP Taq1B polymorphism.
METHODS: A total of 97 patients with CAD and 43 healthy volunteers were included in the study. Traditional risk factors for CAD (age, gender, smoking, hypertension) were evaluated in the patient group. Oxidative markers of LDL were determined in both groups, as well as routine biochemical parameters. Following DNA extraction from white cells, CETP Taq1B polymorphism was determined using polymerase chain reaction amplification and restriction enzyme digestion. Fragments 174 and 361bp were identified as B1, and unrestricted 535 bp fragments as B2.
RESULTS: There was no statistical significance between the B1B1, B1B2, B2B2 genotypes in the patient group in terms of body mass index, waist-to-hip ratio, or biochemical parameters. Though the HDL cholesterol levels were higher in the B2B2 genotype, there was no statistically significant difference in comparison with the control group.
DISCUSSION AND CONCLUSION: The genetic polymorphism of CETP had no significant effect on CETP function and the CETP polymorphism should not be proposed as an independent risk factor for cardiovascular events.

INTRODUCTION: The aim of the present study was to compare the stability of 7 routine analytes using a BD Vacutainer Barricor plasma blood collection tube, a BD Vacutainer SST (Becton Dickinson and Company, Franklin Lakes, NJ, USA) and a Vacusera SST ((Disera A.S., Izmir, Turkey).
METHODS: Five mL blood samples from 60 volunteers were collected into the 3 tubes. Glucose, urea, creatinine, lactate dehydrogenase (LD), sodium (Na), chloride (Cl) and potassium (K) levels were analyzed at 0, 4, 8, and 12 hours on a Cobas 8000 analyzer ((F. Hoffmann-La Roche Ltd., Basel, Switzerland). Bias and bias% results were calculated and compared to clinically acceptable limits (CAL).
RESULTS: Intraclass correlation results revealed excellent agreement in the 7 chemistry analytes between the 3 tubes (0.863-1.000). The CAL for Cl, creatinine, glucose, K, LD, Na and urea are 3 mmol/L, 10%, 0.3 mg/dL, 10%, 0.5 mmol/L, 20%, 3 mmol/L and 2mg/dl, respectively. At the 12th hour, there was a difference observed in glucose between Barricor-SST and Barricor-Vacusera SST were 10.06 mg/dL (11.38 %) and 11.14 mg/dL (-12.76%). Analytical coefficient (CV) of variation results for glucose, LD, creatinine, urea, Na, K, and Cl were 3.22%, 5.80%, 5.28%, 3.90%, 2.00%, 1.95%, and 1.37% respectively.
DISCUSSION AND CONCLUSION: Although the stability of all 7 analytes was within the CAL during a 12-hour period, clinically different results were obtained. In terms of stability evaluation, the use of plasma might be preferable in clinical laboratories. The routine chemistry analytes studied were within the clinically acceptable range in both plasma and serum specimens, but validation and estimation of reference intervals for plasma tubes are needed.

INTRODUCTION: Vitamin D has an important effect on calcium (Ca) and phosphorus (P) metabolism and bone health. It helps regulate the ratio of Ca and P. The aim of this study was to investigate the effects of vitamin D and minor surgical stress on Ca and P levels in the liver, kidneys, and serum in 24 New Zealand rabbits with cartilage defects.
METHODS: Experimental groups of MFS (only microfracture surgery), Vit D (only oral vitamin D supplementation), and MFS+Vit D (both microfracture surgery and oral vitamin D supplementation) were created. The levels of Ca and P in serum, liver, and kidney samples were measured using a spectrophotometric method.
RESULTS: The kidney Ca/P ratio was lower and the serum Ca/P ratio was higher in the MFS+Vit D groups than in the control group. The serum P level was significantly lower in the MFS and MFS+Vit D groups when compared with the control group.
DISCUSSION AND CONCLUSION: To the best of our knowledge, this is a novel study examining microfracture surgery and the effect on Ca and P. The Ca/P ratio revealed clinically valuable information about the important balance between Ca/P ratio and the adequacy of vitamin D. Vitamin D supplementation before microfracture surgery may be beneficial and may prevent a de creased Ca/P ratio due to the effect of surgical stress.

INTRODUCTION: Vitamin D is known to be an essential element for calcium metabolism and bone health. Recent studies have also identified vitamin D deficiency as a risk factor for cancers, autoimmune diseases, and cardiovascular disorders. The aim of this study was to investigate the relationship between vitamin D status and thyroid disease.
METHODS: A total of 1197 adults aged 18-45 years were enrolled in this retrospective study. Data of serum levels of vitamin D, free triiodothyronine, free thyroxine, and thyroid-stimulating hormone were retrieved and analyzed. The individuals were divided into 3 groups: euthyroid state (n=940), hypothyroidism (n=206), and hyperthyroidism (n=51). The vitamin D status of the groups was compared.
RESULTS: The study population had a mean serum vitamin D concentration of 18.33±14.53 ng/mL. The mean vitamin D level was 16.01±14.37 ng/mL in females (n=921) and 26.04±12.26 ng/mL in males (n=276) (p<0.001). The mean vitamin D level in the euthyroid, hypothyroidism, and hyperthyroidism groups was 8.79±15.04 ng/mL, 15.72±11.71 ng/mL, and 20.4±14.23 ng/mL, respectively. There was a statistically significant difference in the vitamin D level between the hyperthyroidism and hypothyroidism groups (p<0.05).
DISCUSSION AND CONCLUSION: Vitamin D deficiency/insufficiency is an important public health problem in Turkey, especially in females. The hypothyroid patients had significantly lower vitamin D levels compared with the other groups. Vitamin D supplementation may be considered in the treatment of thyroid disease; however, additional prospective studies with a larger number of subjects are needed.

INTRODUCTION: The aim of this study was to determine the median values of the maternal serum triple screen test components, beta human chorionic gonadotropin (β-hCG), alpha-fetoprotein (AFP), and unconjugated estriol (uE3), at a single hospital in order to enhance prenatal diagnostic ability and to report fetal anomaly risks more accurately and reliably.
METHODS: The triple test results of 692 pregnant women were evaluated retrospectively. The median values specific to a single laboratory were determined and compared with those of a fetal risk assessment software program.
RESULTS: The laboratory estimated β-hCG medians according to gestational week were higher than those of the 14th and 16th week generated by the software program and lower in the other weeks. The serum estimated medians for AFP were higher than those of the program in all weeks except the 14th week. The difference between weeks 15, 16, and 17 was significant (p<0.001). For uE3, the estimated medians were lower than the software results and the difference was significant at weeks 15, 16, 17, and 18 (p<0.001).
DISCUSSION AND CONCLUSION: The determination of regional median values would provide more accurate and reliable results for prenatal screening tests.

INTRODUCTION: Anamnesis, physical examination and radiological examination are generally sufficient to diagnose a cystic lesion in the neck. Fine needle aspiration (FNAB) biopsy is a diagnostic tool in the management of neck masses when indicated.
METHODS: 61 years old male patient admitted to our hospital because of a lesion in the neck region. The patient was unwilling for the excision of the lesion that a FNAB was performed. 4 cc opaque white material was sent to pathology and a portion of 1 cc was separated for chemical analysis for thyroglobulin and thyroid hormones.
RESULTS: Results showed that the cyst material contained 0,72 ng/mL thyroglobulin (1,6-50 ng/mL serum normal values), a free T4 level (0,55 ng/dL ) lower than the patients serum free T4 value (1,11 ng/dL) and a free T3 level (3,13 pg/mL) higher than the patients serum free T3 value (2,74 pg/mL). Cytology report confirmed a benign lesion.
DISCUSSION AND CONCLUSION: FNAC is a diagnostic tool in the management of neck masses. Currently, chemical analysis of aspiration material has very limited usage, but technical developments and new applications promise an extra aid in differential diagnosis of problematic lesions. If a FNAB is performed with any reason, it should be kept in mind that the aspiration material is probably suitable for chemical analyses of various parameters.

Biotin is a water-soluble vitamin that is an essential coenzyme in the transfer of carboxyl groups by several carboxylases involved in the synthesis of fatty acids, gluconeogenesis, amino acid metabolism, and the citric acid cycle. In the last decade or so, several reports have highlighted biotin interference causing clinically incompatible immunoassay test results. The underlying reason for this relatively new issue of biotin interference is thought to be related to the widespread use of high-dose biotin, which has led to the potential for biotin interference in routine immunoassays that use a biotin-streptavidin interaction. In November 2017 and November 2019, the US Food and Drug Administration warned the public, healthcare providers, laboratory personnel, and kit manufacturers about biotin interference and its importance. Awareness of biotin interference among laboratory staff and clinicians can prevent misdiagnosis and inappropriate treatment. The vulnerability of an immunoassay test to biotin interference is not constant; the test results may be incorrectly high or low, depending on the assay technology. Biotin can be a challenging source of interference and analytic error in terms of detection and prevention. Laboratory staff should be informed about this potential interference in immunoassays using biotin-streptavidin linkage. To reduce the likelihood of erroneous results, particular attention must be given to the test results of certain patients (e.g., patients with multiple sclerosis) or those that are not compatible with the clinical findings. To mitigate this patient safety risk, laboratories using methods vulnerable to biotin interference should develop appropriate solutions to detect and overcome biotin interference.