Serum Separation Research Articles

Pre-analytical stability of haematinics, lactate dehydrogenase and phosphate in whole blood at room temperature up to 24 h, and refrigerated serum stability of lactate dehydrogenase, folate and vitamin B12 up to 72 h using the CRESS checklist.

There is a lack of analyte stability data in whole blood (WB). The aim of this study was to determine the allowable delay in WB processing for lactate dehydrogenase (LDH), folate, vitamin B12, iron and phosphate measurement. The stability of LDH, folate and vitamin B12 was also assessed in stored serum at clinically relevant time points. Blood was taken from n=10 volunteers into Sarstedt serum gel tubes. We assessed stability in WB at room temperature up to 24 h, and stability in refrigerated serum up to 72 h. Mean percentage deviation at each time point was compared to criteria for minimum allowable bias. Results produced from one individual were removed due to discordant results, leaving n=9 specimens at each time point. Stability of folate and phosphate was variable in WB across 24 h, but was deemed to be clinically acceptable. LDH was unstable in WB, iron was stable for at least 12 h, and vitamin B12 and ferritin were acceptable for up to 24 h. Serum LDH, folate and vitamin B12 all demonstrated acceptable stability in refrigerated serum stored for up to 72 h. Blood should ideally be centrifuged within 7 h for phosphate, LDH and folate, and 12 h for iron. However, for phosphate, folate and iron, there is likely to be little clinical impact if serum separation is delayed up to 24 h. Further research is needed to assess LDH stability in WB at 0-12 h, but changes are minimal at 12 h. All other analytes assessed showed acceptable stability across the time-points tested.

Differences Between Serum and Plasma: An Indirect Approach to Derive a Combined Reference Interval for Total Protein, Albumin, and Globulin

Abstract The objective of our study is to derive reference intervals (RI) for total protein (TP), albumin and globulin that are appropriate for both plasma and serum samples by applying statistical analyses to retrospective patient data. Both plasma and serum are acceptable matrices for these tests at our institution, with a single RI that applies to all specimens. The widespread shortage of lithium heparin (LH) tubes that occurred as a consequence of the pandemic prompted our lab to switch the primary tube type for comprehensive metabolic panels (CMPs) from LH to serum separator tubes (SST) in October 2021. The primary tube type reverted to LH in October 2023, and no adjustments were made to RIs at either time. To determine how well our RIs align with the accepted matrices, we used R Statistical Programing version 4.3.1 to apply an indirect, nonparametric statistical approach to data extracted from the laboratory information system (LIS) between July 2018 and December 2023. All orders for TP, albumin and globulin were queried to include the following components in the analysis: TP, albumin, globulin, serum TP, serum albumin and serum globulin. The records were divided into 3 epochs based on the primary tube type for CMP on the order date, with epochs 1 and 3 reflecting LH and epoch 2 reflecting SST. We attempted to identify a subset of serum and plasma samples in healthy individuals by applying exclusion criteria based on inpatient status, age, and draw station at which the specimen was collected. For each component, a resampling bootstrap method was used to calculate the RIs and corresponding 95% confidence intervals by epoch. Our results show that the RI of TP, albumin and globulin changed significantly between the epochs, reflecting the difference in primary matrix. The components serum TP, serum albumin, and serum globulin did not see a significant change in values over the epochs. A verification study looking at plasma and serum samples in 20 healthy individuals support these results. Based on these findings, our reference intervals were updated from 6.6-8.7 g/dL to 5.9-8.3 g/dL for TP, from 3.6-4.9 g/dL to 3.6-5.1 g/dL for albumin and from 2.3-3.5 g/dL to 1.5-3.9 g/dL for globulin. We show that there are statistically and potentially clinically significant differences in the reference intervals of TP, albumin and globulin in serum compared to plasma. This study demonstrates a big data analytics approach to derivation of RIs and emphasizes the importance of RI assessment and adjustment for patient population and acceptable specimen type.

Accuracy of Transforming Growth Factor-Beta in Serum and Synovial Fluid as Rheumatoid Arthritis Prognostic Factors

Background: Rheumatoid arthritis (RA) An autoimmunity of the joints which is now seen as a major public health concern. Therefore, finding new biomarkers is crucial to improve RA sufferers' quality of life. Several cytokines increased the inflammatory cascade which linked to pathophysiology of RA. This investigation aimed to determine the validity of transforming growth factor-beta-1 (TGF-β1) in synovial fluid and serum as prognostic factor and which one is better for rheumatoid arthritis disease follow up. Material and Methods: In Al-Saddar Medical City Rheumatology Unit in the Najaf governorate, 80 patients were included in case-control research. These patients were identified by specialized who classified the patients according to stages of disease into mild stage (stage 1 and 2) and aggressive (stage 3 and 4 who had knee effusion and synovial fluid separation). Venous blood samples (3ml) drawn from patients and controls were transferred to a gel tube for serum separation that used to measure the TGF-β1 level in accordance (BT LAB/China), RF level and anti-CCP level by ELISA assay. knee synovial fluid was collected from RA patients in aggressive stage and from patient suffering from knee trauma as control group which included 18 patients not have RA. The result demonstrated that Females and aged individuals in AL-NAJAF province more incidence with RA disease. TGF-β1 serum level increased significantly with disease severity and positive correlated with ACCP autoantibody, according to ROC prognosis analysis AUC of TGF-β1 serum level was excellent 0.9 with 100% sensitivity and specificity. While ROC analysis for TGF-β1 synovial fluid was 0.8 with 77.8% sensitivity and 86.7% specificity Conclusion: Using ROC analysis, which supported good TGF level in both serum and synovial fluid diagnosis accuracy and enabled more sensitive and precise discrimination in RA disease. Instead of using synovial fluid separation as a diagnostic for excellent prognosis in RA disease, TGF-β1 and ACCP blood levels can help patients avoid discomfort and stress.

A-070 Evaluation of Plain and Serum-Separator Blood Collection Tubes for the Measurement of Steroid Hormones by Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS)

Abstract Background Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) is the preferred method for quantifying steroids. Commonly measured steroids 11-deoxycortisol, androstenedione, testosterone, 17-hydroxyprogesterone and dehydroepiandrosterone (DHEA). Although serum separator blood collection tubes may not be recommended but their frequent use is attributed to the ease of serum separation. Moreover, the serum separator tube may be the only available option for analysis, without the need for additional sample collection. Under such conditions, from certain serum separator tubes, we observed occasional interference in LC-MS/MS steroid method. We pursued to evaluate the performance of blood collection tubes without and those with serum separators, for the quantification of specified steroids by LC-MS/MS. Methods Blood samples were collected from 10 volunteers using both plain and serum separator blood collection tubes procured from two major suppliers (Greiner and BD). The specified steroids were measured by LC-MS/MS method. The procedure involved addition of labeled internal standards to the samples and extraction of steroids in methyl tert-butyl ether. Subsequently, the extract dried under a stream of nitrogen, and the residue was reconstituted in the mobile phase. LC-MS/MS analysis involved multiple reaction monitoring (MRM) for the specified steroids and their internal standards. Results The figure shows a sample chromatogram from a subject with blood samples collected in a plain (A) and serum separator tubes from Greiner (B) and BD (C1 and C2, a zoomed of C1). In this sample, from the plain tube, the concentrations of 11-deoxycortisol, androstenedione, testosterone, 17-hydroxyprogesterone and DHEA were 27, 55, 690, 99 and 283 ng/mL respectively. No significant interference was observed in Greiner serum separator tube. Whereas BD serum separator tube exhibited several erroneous peaks making the quantitation of several steroids challenging or inaccurate. Conclusions In the described LC-MS/MS method, BD serum-separator tubes exhibited erroneous peaks. These peaks were not seen in Greiner serum-separator tubes.

B-357 Siemens CA 72-4: an assay for measurement of Tumor Associated Glycoprotein (TAG) 72

Abstract Background The tumor associated glycoprotein (TAG) 72, also known as CA 72-4 is a mucin protein of high molecular weight. CA 72-4 is found on the surface of many cancer cells, including stomach (gastric), ovary, breast, colon and pancreatic cells. CA 72-4 is currently one of the primary markers for the diagnosis of gastric cancer and monitoring the course and efficacy of gastric cancer. In ovarian cancer, it has a higher sensitivity for mucin- type ovarian cancer, and its combination with CA125 for detection can significantly improve the clinical sensitivity. In colorectal cancer, CA 72-4 combined with CEA detection was also found to significantly improve the sensitivity of the initial diagnosis. An assay for CA 72-4 on Siemens Atellica IM (Siemens CA 72-4) is being developed and analytical performance is being presented. Methods The Siemens CA 72-4 assay (in development) is a one-step chemiluminescent microparticle immunoassay (CMIA) for the quantitative determination of CA 72-4 in human serum and plasma. The specimen is incubated with paramagnetic microparticles coated with the monoclonal antibody (mAb) B72.3 and acridinium-labeled mAb CC49 conjugate on the Siemens Atellica IM® System. After incubation and washing, Acid and Base reagents are added. The resulting relative light units (RLUs) are directly proportional to the amount of CA 72-4 in the sample allowing for the quantitative determination of CA 72-4 in the specimen. Results The following performance were determined using 3 unique lots of reagents and calibrators with the calibration range for the assay being 0.00 to 200.00 U/mL. The limit of blank (LoB), limit of detection (LoD), and limit of quantitation at 20% CV (LoQ) were determined and met the goal of ≤ 1.00 U/mL. Linearity according to CLSI EP06 Ed2 was demonstrated for a range of 1.00 through 200.00 U/mL. A Precision study of 2 controls and 5 panels spanning the range of the assay demonstrated a total %CV ≤ 6% for samples ≥ 5.00 U/mL and ≤ 0.25 SD for samples <5.00 U/mL. In the sample tube type study, a matrix comparison of 23 matched serum and plasma samples were evaluated. Passing-Bablock slopes of < 8% and r > 0.99 were observed when evaluating samples within the measurement range for plasma (LiHep, LiHep separator, K2EDTA and K3EDTA) tubes and serum separator tubes (SST) compared to the Red Top serum samples. Five endogenous substances were evaluated for interference in the CA 72-4 assay. The average percent difference between test and control samples for all endogenous interferents was < 10%. Percent difference in the presence of 28 potentially interfering drugs was ≤ 4.0%. Conclusions The Siemens CA 72-4 assay currently in development is a sensitive and precise assay for the quantitative determination of CA 72-4 in human serum and plasma.

B-358 Siemens NSE: an assay for measurement of human Neuron-Specific Enolase

Abstract Background Neuron-specific enolase (NSE), a glycolytic enzyme (2-phospho-D-Glycerate hydrolase) can be found in a variety of non-neuroendocrine cells. Determination of NSE is used for monitoring response to therapy and detection of recurrent disease, such as SCLC and neuroendocrine tumors. An assay for NSE on Siemens ADVIA Centaur® XPT System and Siemens Atellica® IM system (Siemens NSE) is being developed and analytical performance is being presented. Methods The Siemens NSE assay (in development) is a one-step chemiluminescent microparticle immunoassay (CMIA) for the quantitative determination of NSE in human serum. The specimen is incubated with paramagnetic microparticles coated with the monoclonal antibody (mAb) NSE21, and acridinium-labeled mAb NSE17 conjugate on the Siemens ADVIA Centaur XPT system and Siemens Atellica IM system. After incubation and washing, Acid and Base reagents are added. The resulting relative light units (RLUs) are directly proportional to the amount of NSE in the sample allowing for the quantitative determination of NSE in serum. Results The following performance were determined using 3 unique lots of reagents and calibrators with the calibration range for the assay being 0.0 to 400.0 ng/mL. For the ADVIA Centaur XPT and Atellica IM systems were shown to be equivalent within 2%. The limit of blank (LoB), limit of detection (LoD), and limit of quantitation at 20% CV (LoQ) were determined and met the goal of ≤ 1.6 ng/mL. Linearity according to CLSI EP06 Ed2 was demonstrated for a range of 1.6 through 400.0 ng/mL. A Precision study of 2 controls and 6 panels spanning the range of the assay demonstrated a total %CV ≤ 7% at all levels. Comparison of 50 specimens collected in Red Top serum and Serum Separator Tubes (SST) had a Passing-Bablock slope of < 2% and r of > 0.99 when evaluating samples within the measurement range. Five endogenous substances were evaluated for interference in the Siemens NSE assay. The average percent difference between test and control samples for all endogenous interferents was < 10%. Percent difference in the presence of 38 potentially interfering drugs was ≤ 10.0%. The potential cross-reactant αα enolase was evaluated at concentration of 900 ng/mL and the percent cross-reactivity was ≤ 2%. Conclusions The Siemens NSE assay currently in development is a sensitive and precise assay for the quantitative determination of NSE in human serum.

B-356 Siemens CYFRA 21-1: an assay for measurement of cytokeratin fragment 21-1

Abstract Background Cytokeratins are structural proteins forming the subunits of epithelial intermediary filaments. The soluble fragment of cytokeratin 19, cytokeratin fragment 21-1 (CYFRA 21-1), can be found in the blood of lung cancer patients, primarily those with non-small cell lung cancer (NSCLC). CYFRA 21-1 is the preferred biomarker in the management of NSCLC, particularly squamous cell and large cell carcinoma subtypes. An assay for CYFRA 21-1 on Siemens ADVIA Centaur® XPT and Siemens Atellica® IM (Siemens CYFRA) is being developed and analytical performance is being presented. Methods The Siemens CYFRA 21-1 assay (in development) is a one-step chemiluminescent microparticle immunoassay (CMIA) for the quantitative determination of CYFRA 21-1 in human serum and plasma. The specimen is incubated with paramagnetic microparticles coated with the monoclonal antibody (mAb) BM19.21 and acridinium-labeled mAb KS19.1 conjugate on the Siemens ADVIA Centaur XPT System and Siemens Atellica IM System. After incubation and washing, Acid and Base reagents are added. The resulting relative light units (RLUs) are directly proportional to the amount of CYFRA 21-1 in the sample allowing for the quantitative determination of CYFRA 21-1 in the specimen. Results The following performance were determined using 3 unique lots of reagents and calibrators with the calibration range for the assay being 0.00 to 100.00 ng/mL. For the ADVIA Centaur XPT and Atellica IM systems were shown to be equivalent within 4%. The limit of blank (LoB), limit of detection (LoD), and limit of quantitation at 20% CV (LoQ) were determined and met the goal of ≤ 1.00 ng/mL. Linearity according to CLSI EP06 Ed2 was demonstrated for a range of 0.66 through 100.00 ng/mL. A Precision study of 2 controls and 5 panels spanning the range of the assay demonstrated a total %CV ≤ 8% at all levels. In the sample tube type study, a matrix comparison of 61 matched serum and plasma samples were evaluated. Passing-Bablock slopes of < 5% and r > 0.99 were observed when evaluating samples within the measurement range for plasma (LiHep, LiHep separator, K2EDTA and K3EDTA) tubes and serum separator tubes (SST) compared to the Red Top serum samples. Six endogenous substances were evaluated for interference in the CYFRA 21-1 assay. The average percent difference between test and control samples for all endogenous interferents was < 10%. Percent difference in the presence of 20 potentially interfering drugs was ≤ 4.0%. Conclusions The Siemens CYFRA 21-1 assay currently in development is a sensitive and precise assay for the quantitative determination of CYFRA 21-1 in human serum and plasma.

Multiple Myeloma Presenting as a Spheno-Orbital Plasmacytoma and Improper Serum Separation: A Case Report

Multiple Myeloma Presenting as a Spheno-Orbital Plasmacytoma and Improper Serum Separation: A Case Report

Evaluation of serum IL 18 / IL 18 binding protein ratio and their relation with IL- 18 gene polymorphisms in sample of Iraqi type 2 diabetes mellitus patients. A case control study.

To evaluate the ratio of interleukin18 and interleukin18 binding protein in type 2 diabetes mellitus patients, and its relation with the presence of interleukin18-607C/A and interleukin18-137G/C gene polymorphisms and the type of complications. The case-control study was conducted at the endocrinology clinic of the Madinat Al-Imamin Al-Kazemin Teaching Hospital, Iraq, from September 2020 to July 2021, and comprised diagnosed patients of type 2 diabetes mellitus, and healthy controls matched for age and gender. Blood samples were obtained that were processed for serum separation. Serum interleukin18 and interleukin18 binding protein levels were assessed, and part of the sample was used for deoxyribonucleic acid extraction using tetra-primer amplification refractory mutation system polymerase chain reaction with four specific primers for interleukin18-607C/A and interleukin-18-137G/C gene polymorphisms in both the groups. Data was analysed using SPSS 20. Of the 168 subjects, 86(51.2%) were patients; 67(77.9%) females and 19(22.1%) males with mean age 52±8.97 years. There were 82(48.8%) controls; 56(68.3%) females and 26(31.7%) males with mean age 48±9.44 years (p>0.05). Higher serum level of interleukin18 and lower level of interleukin18 binding protein were seen in type 2 diabetes mellitus group compared to the controls (p<0.001). Interleukin18-137G/C and interleukin18-607C/A mutant alleles had odd ratios 3.52 (confidence interval: 1.91- 6.63) and 3.25 (confidence interval: 1.77-5.83), respectively, as risk factors for the occurrence of type 2 diabetes mellitus. There was an association of interleukin18- 137G/C homozygous mutant genotype with the occurrence of retinopathy among type 2 diabetes mellitus patients (p=0.046), but risk allele C was not associated with retinopathy (p>0.05). The presence of interleukin18-137G/C and interleukin18-607C/A gene polymorphism might be considered a risk factor for type 2 diabetes mellitus.

Cellulose acetate electrophoretic separation of serum and urine proteins in Nigerian children with autism spectrum disorders

BackgroundAutism spectrum disorder (ASD) is a neurodevelopmental disorder (NDD) characterized by social communication challenges and restricted, repetitive behaviors. While genetic and environmental factors are known to contribute to ASD, the role of the immune system remains unclear. This study investigated the separation patterns of serum and urine proteins in Nigerian children with ASD compared to typically developing children and children with other NDDs.MethodsForty-seven participants aged 3–8 years were recruited, including 16 children diagnosed with ASD and 16 children with other NDDs, both according to DSM-5 criteria, along with 15 neurotypical children. Blood and urine samples were collected for protein analysis. Total protein and albumin levels were measured in both serum and urine using established methods. Protein separation in serum and urine was performed using cellulose acetate electrophoresis, followed by densitometry analysis of the electrophoretic patterns.ResultsThe results revealed no significant differences in total serum protein levels and most protein fractions between the groups. However, children with other NDDs exhibited significantly lower levels of alpha-2 globulin compared to neurotypical children. Conversely, both ASD and NDD groups showed significantly higher gamma globulin levels compared to the control group. Interestingly, spot urine protein levels were significantly higher in children with ASD compared to neurotypical children.ConclusionThe observed changes in alpha-2 and gamma globulin levels suggest potential immune system involvement in ASD and other NDDs. The higher urine protein excretion in the ASD group warrants further investigation to explore the potential of urinary protein biomarkers for ASD diagnosis.

Molecular insight of miRNA-217 role in the pathogenesis of myocardial infarction: Promising diagnostic biomarker and therapeutic target

BackgroundGlobally, myocardial infarction (MI) is one of the main causes of death. This study aims to investigate the role of miR-217 in the pathogenesis through targeting MAPK and PI3K/AKT signaling pathways in experimental model of myocardial infarction and studying the possible cardioprotective role of dihydromyricetin (DHM) through modulation of this pathway. MethodsDihydromyricetin was injected (100 mg/kg; p.o.) in isoprenaline induced myocardial infarction rat model for 14 days. Rats were anaesthetized and blood samples were taken for serum separation, estimation of creatine kinase-MB (CK-MB), and troponin-I levels after 24 h had passed since the last isoprenaline injection. In addition, the hearts were also used for the other biochemical studies and the histological evaluation. ResultsDHM resulted in a significant suppression of the elevated levels miR-217 and MAPK compared to the MI control group and restored the normal level of serum CK-MB. Furthermore, DHM successfully restored the oxidative balance and halted the pro-inflammatory mediators in the cardiac tissue. ConclusionAccordingly, our experiment emphasizes the anti-ischemic property that has been demonstrated through modulation of expression level of miR-217 and consequent deactivation of MAPK and PI3K/AKT signaling pathways, and this was assured by halting downstream pro-inflammatory markers.

INVESTIGATION OF USAGE OPPORTUNITIES OF DIFFERENT PROPORTIONS OF WHEY AND CHIA SEED FLOUR IN BUTTERMILK

In this study, it was aimed to obtain a functional beverage with high nutritional value by using whey and chia seed flour in the production of buttermilk. In addition to its high nutritional value, while preventing whey from causing environmental pollution as a waste material, it is aimed to obtain a new dietary product with chia seed flour containing 34-40g fiber per 100g, antioxidant, omega-3 fatty acid and rich protein content. Experimental buttermilk samples were prepared by adding whey (PAS) and chia seed flour at different rates. K (control group), K2 (%1 Chia seed meal), K3 (%0,5 Chia seed meal), Group 1 (25% Whey + %1 Chia seed meal), Group 2 (25% Whey + %0,5 Chia seed meal), 3. Group (50% Whey + %1 Chia seed meal), 4.Experimental groups prepared as a group (50% Whey + %0,5 Chia seed flour) were kept at +4 ̊C and their physical, chemical and sensory properties were examined on the 1st, 3rd, 5th, 7th and 14th days. In the experimental buttermilk samples we researched, the use of whey and chia seed flour was found to have a significant effect on psychrophilic bacteria count (log cfu/ml), coliform group bacteria (log cfu/ml), yeast-mold count (log cfu/ml), lactobacil spp. (log cfu/ml) and lactococ spp. (log cfu/ml), pH, acidity (lactic acid), water-soluble dry matter (%), serum separation (%), color values (L*, a*, b*) and sensory properties (p

HEMATOLOGY AND BIOCHEMICAL REFERENCE INTERVALS FOR FREE-RANGING PRONGHORN (ANTILOCAPRA AMERICANA) IN WEST TEXAS.

Pronghorn (Antilocapra americana) are considered a keystone species of North American grasslands and an important economic source for many landowners in Texas. Pronghorn restoration projects routinely capture and translocate individuals from surplus populations to restoration areas. The objective of this study was to generate normal hematological and biochemical reference intervals (RI) for free-ranging pronghorn populations in Texas as a health monitoring tool for pronghorn restoration efforts. Blood samples were collected by jugular venipuncture and divided among an EDTA tube, serum separator tube, and a single blood smear on site. Complete blood counts and biochemical profiles were completed at the Texas Veterinary Medical Diagnostic Laboratory. In total, 417 individuals (41 males, 376 females) were included in the analysis. RI were determined by robust methods (R Studio) and mixed models' analysis of variance (SPSS 28) to examine differences in blood parameters due to fever, sex, age (adult versus yearling [<1 yr of age]), cell abnormalities, and pathogen exposure reported by the testing laboratory. Sex, age, and pathogen exposure affected mean blood values, but did not warrant development of separate RI by class. Bluetongue virus was identified in 46.8% (195/417) of pronghorns and epizootic hemorrhagic disease in 89.4% (194/217) of pronghorns; 84.8% (184/217) of the pronghorns tested positive for both diseases. This information provides baseline hematology and biochemical parameters to assess the health of free-ranging pronghorn and guide wildlife managers in decision-making for future translocations and restoration objectives.

Platelet-Rich Plasma (PRP) Based on Simple and Efficient Integrated Preparation Precises Quantitatively for Skin Wound Repair.

Platelet-rich plasma (PRP) has become an important regenerative therapy. However, the preparation method of PRP has not been standardized, and the optimal platelet concentration for PRP used in skin wound repair is unclear, leading to inconsistent clinical efficacy of PRP. Therefore, the development of standardized preparation methods for PRP and the investigation of the dose-response relationship between PRP with different platelet concentrations and tissue regeneration plays an important role in the development and clinical application of PRP technology. This study has developed an integrated blood collection device from blood drawing to centrifugation. Response surface methodology was employed to optimize the preparation conditions, ultimately achieving a platelet recovery rate as high as 95.74% for PRP (with optimal parameters: centrifugation force 1730× g, centrifugation time 10 min, and serum separation gel dosage 1.4 g). Both in vitro and in vivo experimental results indicate that PRP with a (2×) enrichment ratio is the most effective in promoting fibroblast proliferation and skin wound healing, with a cell proliferation rate of over 150% and a wound healing rate of 78% on day 7.

Assessing the stability of uncentrifuged serum and plasma analytes at various post-collection intervals

Abstract Objectives Our study aimed to assess the stability of 26 biochemistry analytes in serum or plasma samples separated from blood samples centrifuged at different time intervals after collection, simulating sample transport via despatch delivery systems. Methods Blood from forty-one volunteers were collected using five serum separator tubes (SST) and five fluoride oxalate tubes (FOT) for each volunteer following written informed consent. Each of the five tubes in both groups of SST and FOT was centrifuged at one of the time intervals: 0.5 h, 4 h, 8 h, 12 and 24 h after collection. These samples were left standing prior to centrifugation at room temperature. We calculated the percentage difference for each analyte between the 0.5 h and other time intervals to assess analyte stability. The percentage difference was compared to the desirable specification for bias and reference change value (RCV). Results Mean concentration of serum potassium showed a significant increase in the percentage RCV after 8 h, while CKMB showed an increase after 12 h of delayed centrifugation compared to the baseline (0.5 h). There were no significant percentage RCV for the other analytes at all timelines. Conclusions Serum potassium and CKMB were stable up to 8 and 12 h of delayed centrifugation respectively whilst all other analytes appear stable up to 24 h, suggesting that sample transport delay of up to 8 h, with the condition that room temperature is maintained, may not have a significant impact on accuracy of the biochemistry/immunochemistry test results.

Evaluation of Direct Antimicrobial Susceptibility Testing of Gram-Negative Bacilli and Staphylococcus aureus from Positive Pediatric Blood Culture Bottles Using BD Phoenix M50.

Bloodstream infections (BSIs) are life-threatening infections for which a timely initiation of appropriate antimicrobial therapy is critical. Antibiotic susceptibility testing (AST) directly performed on positive blood culture broths can help initiate targeted antibiotic therapy sooner than the standard AST performed on colonies isolated on solid media after overnight incubation. Faster antimicrobial susceptibility testing (AST) results can improve clinical outcomes, and reduce broad-spectrum antimicrobial consumption and healthcare-associated costs in sepsis. In this study, we evaluated the accuracy of a direct AST inoculation method on the BD Phoenix M50 system using serum separator tubes to harvest bacteria from positive pediatric blood culture bottles. Direct AST was performed on 132 monomicrobial pediatric blood culture bottles that were positive for Enterobacterales (65; 49.2%), Staphylococcus aureus (46; 34.8%), and non-fermenting Gram-negative bacilli (21; 16%). Overall, the categorical and essential agreements between the direct method and standard method were 99.6% and 99.8%, respectively. Very major, major, and minor error rates were 0.1%, 0.09%, and 0.20% respectively. Direct AST performed on pediatric blood culture bottles using BD Phoenix M50 can quickly provide accurate susceptibility information to guide antimicrobial therapy in patients with BSI.

The Relationship Between Mortality and Leuko-Glycemic Index in Coronary Care Unit Patients (MORCOR-TURK LGI)

Introduction&amp;Objective: Identifying high-risk patients with a poor prognosis in coronary care unit (CCU) patients can assist physicians in providing optimal care and implementing preventive strategies. Leuko-glycaemic index (LGI), synthesized by multiplying the blood glucose level by the leukocyte count, has gained popularity in risk stratification of myocardial infarction patients. In this context, this study was carried out to investigate the relationship between LGI assessed at admission and in-hospital mortality in CCU patients. Methods: This is a multi-center, cross-sectional and observational study. (MORCOR-TURK LGI: Mortality Predictors in Coronary Care in Turkey, ClinicalTrials.gov number NCT05296694). The population of this study consisted of 2917 consecutive patients admitted to the CCU. Blood samples were collected into serum separator tubes in the immediate admission to the CCU. LGI was calculated by multiplying both values and dividing them by a thousand. LGI units were expressed in mg/dl. mm³. The sample was divided into two groups based on the LGI cut-off value of 1.23. Logistic regression analysis was used to find the significant predictors of mortality. Receiver operating characteristics (ROC) curve was to find out the cut-off value of LGI. A p value less than 0.05 was considered to be statistically significant in all analyses. Results: Univariable logistic regression analysis revealed that age, heart failure (HF), LGI, coronary artery disease, hypertension, diabetes mellitus and atrial fibrillation are clinically and statistically significant predictors. Further analysis of these variables using the multivariable logistic regression analysis indicated that age (Odds Ratio [OR]: 1.040, 95% confidence interval [CI]: 1.017-1.063; p=0.001), HF (OR: 2.426, 95% CI: 1.419-4.149; p:0.001) and LGI (OR: 1.349, 95% CI: 1.176-1.549; p3.72 predicted in-CCU mortality with 95.56% sensitivity and 49.19% specificity ([AUC]: 0.659 [95% CI: 0.641–0.676, p

Comparison of the Direct Identification and Short-Term Incubation Methods for Positive Blood Cultures via MALDI-TOF Mass Spectrometry.

Timely pathogen identification in bloodstream infections is crucial for patient care. A comparison is made between positive blood culture (BC) pellets from serum separator tubes using a direct identification (DI) method and colonies on agar plates from a short-term incubation (STI) method with a matrix-assisted laser desorption/ionization Biotyper for the evaluation of 354 monomicrobial BCs. Both the DI and STI methods exhibited similar identification rates for different types of bacteria, except for Gram-positive and anaerobic bacteria. The DI method's results aligned closely with the STI method's results for Enterobacterales, glucose-non-fermenting Gram-negative bacilli (GNB), and carbapenem-resistant Enterobacterales. The DI method exhibited high concordance with the conventional method for GNB identification, achieving 88.2 and 87.5% accuracy at the genus and species levels, respectively. Compared with the STI method, the DI method showed a less successful performance for Gram-positive bacterial identification (50.5 vs. 71.3%; p < 0.01). The DI method was useful for anaerobic bacterial identification of slow-growing microorganisms without any need for colony growth, unlike in the STI method (46.7 vs. 13.3%; p = 0.04). However, both methods could not identify yeast in positive BCs. Overall, the DI method provided reliable results for GNB identification, offering many advantages over the STI method by significantly reducing the turnaround time and enabling quicker pathogen identification in positive BCs.

Sample suitability and stability in different blood collection tubes for methanol, ethanol, isopropanol, acetone and glycols analysis

AimTo systematically examine the sample suitability and stability for volatile alcohols (methanol, ethanol and isopropanol with its metabolite acetone) and glycols (ethylene/propylene glycols, EG/PG) in different collection tubes.MethodTwo pools of...

Effects of Ellagic Acid Supplementation on Antioxidant Status and Symptom Improvement in Patients with Major Depressive Disorder: A Double-blind Randomized Clinical Trial

Background: Depression is one of the most common mood disorders and a major public health concern. Ellagic acid (EA), a type of polyphenol, acts as a strong hydrogen bond network as an electron receptor, enabling it to participate in various reactions. Objectives: Major depression is a critical medical condition that has emerged as a public health issue due to its high incidence, mortality, and suicide rates. One significant factor in the pathogenesis of depression is oxidative stress. This study aimed to evaluate the effects of ellagic acid supplementation on antioxidant status and symptom improvement in patients with major depressive disorder, considering the antioxidant capabilities of ellagic acid. Methods: A total of 40 patients diagnosed with major depressive disorder based on DSM-V criteria were assessed using the Beck Depression and Hamilton Depression Questionnaires. The dietary and caloric intake of the patients were monitored. Additionally, height and weight were measured, and patients with similar age, gender, and weight were matched. The individuals were randomly assigned to either the intervention group or the placebo group using a randomization table. The intervention group received a daily dose of 200 mg of ellagic acid in capsule form. The placebo group received a daily dose of one capsule containing 200 mg of wheat flour, identical in appearance to the intervention substance. The study period lasted for 8 weeks. Venous blood samples were collected before and after the study from all 40 individuals, and after serum separation, oxidative stress markers (malondialdehyde and total antioxidant capacity). were measured using a specific kit and ELISA method. Results: The study results showed a significant reduction in depression scores in the ellagic acid group during the study (P: 0.001)., with these alterations being significant when compared to the placebo group. In the ellagic acid group, a significant increase in total antioxidant capacity (P: 0.027). and a significant decrease in malondialdehyde levels (P: 0.014). were observed at the end of the study, and these changes were significant compared to the placebo group. In contrast, significant changes in total antioxidant capacity and malondialdehyde levels were not observed in the placebo group. Conclusions: The current study indicates that ellagic acid intervention may have a favorable effect on depression in patients with major depressive disorder. This is achieved by reducing BDI scores and serum levels of MDA, as well as increasing serum levels of TAC in these patients compared to the placebo group. However, further investigation is necessary to explore the mechanisms underlying the different alterations of ellagic acid in depression.