Vacutainer Research Articles

B-303 Stability of Antipsychotic Drugs in Patient Serum and Plasma Clinical Samples

Abstract Background Therapeutic drug monitoring (TDM) of antipsychotic blood levels is strongly recommended (clozapine and olanzapine) and recommended (risperidone, aripiprazole, and quetiapine) by ASCP/AGNP Consensus Statement. For effective TDM, it is paramount to understand both the stability of the antipsychotic drugs in serum and plasma, as well as any differences in levels due to sample matrix to ensure robust concentration determinations. While clozapine levels are considered equivalent in serum and plasma, we included in our study four additional antipsychotics. Methods Whole blood samples from ten patients taking clozapine, risperidone, aripiprazole, olanzapine, or quetiapine were collected in one red top tube and in one purple top tube according to an IRB-approved protocol. Samples were then processed within 2 hours of collection to obtain matched serum and K2EDTA plasma samples from each of the patients. CE marked immunoassays for the measurement of clozapine (also FDA cleared), total risperidone/paliperidone, total aripiprazole, olanzapine, and quetiapine were used to quantitate drug concentrations. Stability of the samples was assessed at 4°C, ambient room temperature (ART), and frozen at -80°C, with respect to their Day 0 concentration by measurement of six replicates at each timepoint using the immunoassays. Results Comparison of Day 0 values between serum and plasma for the same patient showed ±9% bias between sample matrices for all drugs, except olanzapine which showed differences up to ±15%. Average bias between serum and plasma was ≤-5% (olanzapine: -9%). All drugs were stable (±15% deviation from Day 0; olanzapine up to ±23%) in serum and in plasma for 7 days at both 4°C and ART and for up to 8 months frozen. Conclusions This study demonstrated that (1) the antipsychotic drugs clozapine, risperidone, aripiprazole, olanzapine, and quetiapine have sufficient stability in both serum and plasma for effective TDM and (2) for TDM, serum or plasma may be used.

Silica and barium: Comparison of microscopic appearance and characterization of effects of silica on cytomorphology.

Silica from plastic red top sample collection tubes and barium cause recognized artifacts in slide preparations for microscopic examination. The objectives of this study were to evaluate and directly compare the microscopic appearance of silica and barium particles and various slide preparation techniques (e.g., use of coverslips, oil immersion, and different stains). A secondary objective of this study was to evaluate the effects of silica particles on cellular morphology after mechanical trauma with cytocentrifugation. Fluid samples (deionized water, pleural effusion, peritoneal effusion, cerebrospinal fluid, and urine) were collected and evaluated in silica- and non-silica-containing tubes. Barium was added to silica and non-silica samples. Direct and cytocentrifuge preparations were compared to evaluate the effect of silica particles on cellular morphology. Preparations were stained with Wright-Giemsa, rhodizonic acid disodium salt, Alizarin Red, Grocott's methenamine silver, and Prussian blue. Silica and barium particles were identifiable via light microscopy with and without polarized light, although silica particles diminished with immersion oil. Barium particles retained their structure and diminished less under oil. Cytoseal mounting medium for coverslip placement resulted in diminished refractility of silica and some barium particles. Silica particles with mechanical interaction during cytocentrifugation resulted in disrupted cellular morphology with many lysed cells. Silica and barium particles were negative for all special stains tested. Silica from plastic red top tubes adversely affects cell morphology in cytocentrifuge preparations, potentially affecting manual differential cell counts and compromising diagnostic interpretation. Samples intended for microscopic evaluation should not be collected in silica-containing tubes.

A-038 An Improved Multiplexed HTLC-HESI-MSMS Method for the Measurement of Total Testosterone in Serum

Abstract Background Testosterone is an anabolic steroid produced primarily in the testicles of males and mainly in the ovaries of females. Imbalance of testosterone is the primary cause of hypogonadism in males, hirsutism and virilization in females, osteoporosis, and diabetes mellitus. Accurate and fast-turnaround measurement of testosterone is critical for diagnosis, prevention, and treatment of testosterone-related diseases in adults and children. In a previous study, testosterone was derivatized with methoxyamine and hydroxylamine in a multiplexed high turbulence liquid chromatography with heated-electrospray ionization-tandem mass spectrometry (HTLC-HESI-MS/MS) method. Using these reagents, differential mass-tagging of testosterone allowed different specimens to be combined in a single injection to increase assay throughput. However, interference was observed for hydroxylamine-derivatized testosterone in serum collected in serum separator tubes (SST). In the current study, our objectives were to (1) replace hydroxylamine with a new derivatizing agent not subject to interference and (2) develop an improved HTLC-HESI-MS/MS method for multiplexed total testosterone measurement. Methods Healthy male and female donor specimens were collected in SST and red-top tubes. Serum was mixed with stable isotope-labeled testosterone as internal standard (ISTD) prior to protein precipitation. Testosterone in the supernatants was derivatized, enriched by solid phase extraction, dried, and reconstituted. Specimens were injected on the HTLC system for on-line extraction, transferred to analytical columns, and eluted using binary gradient. Testosterone derivatives and ISTDs were detected and analyzed on a Triple Quadrupole Mass Spectrometer (Thermo) equipped with HESI. Ionization and multiple reaction monitoring (MRM) scan parameters were optimized for maximized ion transmission and sensitive, specific, and stable quantitation. MRM transitions were used as quantifiers and qualifiers for both testosterone derivatives. Also assessed were ion suppression using T-column infusion, specimen stability by storage in SST tubes at 4 °C, isobaric interference from dehydroepiandrosterone (DHEA), and carryover. Results Intra- and inter-assay coefficients of variation (CV%) for total testosterone levels were <5% at 12, 80, 250, and 1200 ng/dL for both testosterone derivatives. Limits of quantitation (LOQs) for both derivatives were <1 ng/dL. Calibration linearity was verified across the measurement range of 2.5–2000 ng/dL. Both agents were equivalent in derivatizing and recovering testosterone from serum based on a comparison of their quantitative results (R = 0.991, bias = −3.8 ng/dL). No interference was observed in serum collected in SST. Serum specimens collected in SST and red-top tubes from same donors gave equivalent results (R = 0.991, bias = 0.2 ng/dL). Ion suppression was calculated as less than 20% for both derivatives. CV% of the ion-ratios of both derivatives were less than 15% and were stable across the linear range. Testosterone levels were stable in SST for 72 h (at 4 °C) with the serum not separated from the gel. No isobaric interference and no carry over were observed. Conclusion We have developed and validated an improved multiplexed HTLC-HESI-MS/MS testosterone assay using new derivatizing agents. The current method allowed accurate, rapid, specific, and stable analysis of serum total testosterone. SST is an acceptable specimen type for the current method. Precision, accuracy, linearity, ion suppression, and sample stability in SST were validated.

Mitigating Concerns Over Transport Delays: An Analysis of Synovial Fluid Culture Results in Arthroplasty.

There is a concern in the field of arthroplasty that synovial fluid transport delays may reduce the accuracy of synovial fluid culture. However, synovial fluid samples collected in the office, and sometimes in a hospital setting, often require transport to a third-party central or specialty laboratory, causing delays in the initiation of culture incubation. This study investigated the impact of transportation delays on synovial fluid culture results. A retrospective review of prospectively collected data at one clinical laboratory, from 2016 to 2022, was conducted. A total of 125,270 synovial fluid samples from knee arthroplasties, from 2,858 different US institutions, were transported to a single clinical laboratory for diagnostic testing including synovial fluid culture (blood culture bottles). Synovial fluid to be cultured was transported in red top tubes without additives.Samples were grouped into six-time cohorts based on the number of days between aspiration and culture initiation (1-day-delay to 6-day-delay). Metrics such as culture positivity, false-positive culture rate, culture sensitivity, and proportional growth of top genera of organisms were assessed across the cohorts. Of the 125,270 samples in this study, 71.2% were received the day after aspiration (1-day-delay), with an exponential decrease in samples received on each subsequent day.Culture-positive rates for synovial fluid samples received after 1, 2, 3, 4, 5, and 6 days of transport time were 12.2%, 13.3%, 13.5%, 13.1%, 11.6%, and 11.0%, respectively. The maximum absolute difference in culture-positive rate compared to the 1-day-delay cohort was an increase of 1.3% in the 3-day-delay cohort, which was not considered a clinically meaningful difference. The estimated false-positive culture rate remained relatively consistent across time cohorts, with values of 0.3%, 0.4%, 0.3%, 0.2%, 0.5%, and 0.5% for 1, 2, 3, 4, 5, and 6 days of transport time, respectively. None of the cohorts showed a statistically significant difference after adjustment for multiplicity compared to the 1-day-delay cohort.Culture sensitivity was estimated at 68.2%, 67.2%, 70.5%, 70.7%, 65.9%, and 70.7% for 1, 2, 3, 4, 5, and 6 days of transport time, respectively. None of the cohorts showed a statistically significant difference after adjustment for multiplicity compared to the 1-day-delay cohort.Organism proportions were consistent across time cohorts, with Staphylococcus being the most commonly identified organism. No statistically significant differences were found in the proportional contribution of major genera across the cohorts. Synovial fluid culture exhibited surprisingly consistent results despite variable transport time to the destination laboratory, with differences that have minimal clinical importance. While the authors of this study advocate for short transport times as a best practice to expedite diagnosis, it appears that concerns regarding the rapid degradation of culture results due to synovial fluid transportation is unwarranted.

Effect of Prolonged Serum Storage Time and Varied Temperatures on Biochemical Values in African Savanna Elephants (Loxodonta africana)

Blood samples are routinely collected from wild populations in remote locations with limited electricity, minimal diagnostic capabilities, and extreme environmental conditions. Under these conditions, serum samples may be stored for prolonged time under varied temperatures prior to processing, which could affect the ability to interpretation the results. This study’s objective was to evaluate the effects of delayed processing of serum samples and varied storage temperatures on biochemical values in African savanna elephants (Loxodonta africana). Blood samples were collected from six elephants managed by the North Carolina Zoo. For each elephant, seven red top tubes were collected. One serum sample for each elephant was analyzed on Day 0 (control group). The remaining samples were stored under different temperatures including room temperature (23 °C), refrigeration (2.2 °C), and incubation (32.2 °C), with samples from each temperature group being analyzed on Day 5 and Day 10. Many of analytes (10 out of 18) did not change significantly regardless of storage temperature or time. Refrigeration improved stability in an additional four analytes over prolonged storage. We conclude that if serum is properly separated shortly after collection, many serum biochemical analytes can be accurately measured even after suboptimal serum storage, but refrigeration and prompt evaluation are still required for some analytes.

On-Cell Stability for Therapeutic Drug Monitoring

Abstract Introduction A common problem in many clinical laboratories and outpatient clinics is processing specimens rapidly to comply with specimen stability criteria. Labs receive thousands of samples a day and may face challenges with staffing, equipment malfunction, or workflow, which can prevent immediate processing of samples. Currently, for therapeutic drug monitoring, the lab is required to centrifuge specimens and remove the serum/plasma from cells within 2-hours (CLSI-GP44-A4). Many of these drugs are monitored in the outpatient setting, which may require longer transportation times to get specimens from the collection location to the laboratory. This creates challenges for the lab in processing samples within 2-hours and may result in unnecessary rejection of otherwise acceptable specimens. Not all clinical sites have the staffing or space to process the specimens on site. Our objective was to determine if the on-cell stability of therapeutic drugs can be extended to beyond two hours. Methods We performed spiking studies to determine the on-cell stability of phenytoin in whole blood that was collected from healthy donors in barrier-free red top tubes. Phenytoin was spiked into the whole blood at a final concentration of about 10 (therapeutic) or 40 (toxic) µg/mL. The spiked whole blood samples were mixed by inverting six times and then were left at ambient temperature for 30 minutes, 2-, 4-, 6-, or 12-hours, after which they were centrifuged, and the serum was removed for analysis of total phenytoin concentration on the Abbott Architect and free and total phenytoin on the Beckman AU (n=3 per time point and concentration). In vivo studies are ongoing for an extended list of therapeutic drugs, in which two extra red top tubes are collected from patients being monitored for phenytoin, valproic acid, digoxin, vancomycin, lithium, or carbamazepine therapy. The two study tubes are kept at ambient temperature for 6- or 12-hours after collection before being centrifuged and separated from cells. The 6- and 12-hour drug concentrations were compared to the patient’s standard of care tube that was processed within 2-hours, after clotting for 30 minutes. Results Spiking studies demonstrated phenytoin was stable on cells for at least 12-hours at both 10 and 40 µg/mL. The percent total phenytoin remaining at 12-hours relative to the 30-minute control was 104 ± 2% at 10 µg/mL and 99 ± 16% at 40 µg/mL. Furthermore, the fraction of free phenytoin did not change over the 12 hours (10 µg/mL: 8 ± 1% free; 40 µg/mL: 10 ± 1% free). Our preliminary in vivo studies have shown no change in vancomycin or lithium concentration in samples processed 6- and 12-hours post-collection. Conclusion We have demonstrated that phenytoin, vancomycin, and lithium collected in red-top tubes are stable on cells at ambient temperature for at least 12-hours.

Evaluation of hSCRP and microalbumin levels in smokers

Background: Smoking is associated increase in morbidity and mortality from various diseases. Increasing evidence suggests that chronic smoking adversely affects vascular and hormonal systems. Smoking plays a significant role in the development of atherosclerosis, thrombogenesis and vascular occlusion, which further adversely affects the prognosis of nephropathies. Aim and. Objectives: to estimate and compare the levels of hSCRP and microalbumin levels in smokers and non-smokers. Materials and Methods: Under aseptic precautions random venous blood sample of 2 mL was drawn from ante-cubital vein and collected in red top tube and serum was separated and analysed for high sensitivity C reactive protein (hSCRP). Early morning mid-stream urine was used for urine microalbumin estimation and the same sample was used for urine microscopy to exclude patients with urinary tract infection. Statistical Analysis: All statistical tests was performed using SPSS software. For comparisons of different variables student’s t-test and Chi-square test were be used. Pearson coefficient of correlation was used for assessment of relationship between variables. A p value <0.05 was considered statistically significant.

Pregnancy Induced Hypertension and Uric Acid Levels among Pregnant Women Attending Ruhengeri Referral Hospital, in Rwanda.

Background:Pregnancy Induced Hypertension (PIH) is a common burden during pregnancy usually associoted with adverse maternal and paternal outcomes. The uric acid serum level was identified as an important biochemical marker which can predict preeclampsia, a type of PIH. This study was conducted to evaluate the effects of serum uric acid levels in association with blood pressure among pregnant women attending Ruhengeri Referral Hospital.Methodology:A cross-sectional study was designed and 80 pregnant women in different gestation trimesters participated in the study. Data was collected from September to October 2018. Digital sphygmomanometer was used to test blood pressures for participants. Blood samples were collected in red top tubes and centrifuged to obtain serum for uric acid levels. Using Humastar 80, uric acid levels were measured for each participant. Data was analysed using Statistical Package for Social Sciences (SPSS) version 23.0. Bivariate correlation was used to analyse the relationship between uric acid levels and participants’ blood pressure.Results:The median age was 27 in interquartile 23-31 ranging from 19 to 39 years. 58.75% of participants were in their 1st trimester, followed by 21.25% in the 2nd trimester and 20% in the 3rd trimester. The prevalence of hypertension was 11.3% (7.5% for stage 1 and 3.8% for stage 2). Hyperuricemia was found in 15% of the participants. The mean of uric acid level was 7.12 ±1.86 mg/dl in the hypertensive group and 4.49 ±1.22 mg/dl in the non-hypertensive group. The study revealed a strong positive correlation between uric acid levels and systolic/diastolic blood pressure.Conclusion:High prevalence of hypertension among pregnant women was revealed. The association of hypertension and hyperuricemia was recorded with a strong correlation between blood pressures and serum uric acid levels. Examination of Uric acid levels among pregnant women should be routinely performed for early identification and management of hypertension.

Qualification of a 17β-estradiol (E2) Assay in Sprague Dawley Rat Serum

Abstract Introduction/Objective Significant technical issues are associated with methods used for the measurement of estradiol.The objective of this study was to qualify an electrochemiluminescent (ECL) assay for the quantification of 17β-estradiol (E2) in rat serum. Hemolysis has been identified as a factor that interferes with accurate measurement.The impact of hemolysis was also assessed. Methods Approximately 1.0 mL of whole blood was collected from male and female rats into separate red top tubes and processed to serum. The LoQ for E2 was evaluated by analyzing the low calibrator or at least 6 serum samples diluted to produce a value at the low end of the reportable range 8 times in the same run.The mean, standard deviation, and %CV were calculated for each sample.The data set was analyzed by plotting the data and determining the concentration at the intersection of the precision profile curve. Linearity of dilution was performed using commercially available calibration verification material and E2 stripped rat serum.The correlation coefficient, the slope, and the % Nominal were calculated. Intra assay precision was evaluated by analyzing 8 consecutive times in a single run one rat serum sample that was not diluted or spiked. This analysis was performed during the evaluation of the LoQ.The mean, SD and %CV were calculated. The interference of hemolysis with the E2 assay was tested by analyzing at least 5 rat serum samples/pools spiked with hemolyzed rat serum at different hemoglobin concentrations.The %RE was calculated. Results The LoQ assays were acceptable. For all samples tested, the % CV was less than or equal to 25%.The LoQ was verified to be 8.50 pg/mL. The %CV was 15.6%. For samples with estradiol concentrations below the LoQ, a value of 4.25 pg/ml was reported. Linearity of dilution for E2 was acceptable.The correlation coefficients were greater than or equal to 0.9000, the slopes were between 0.7500 and 1.2500, and the % nominals for each level were between 75-125%. The intra-assay precision was considered acceptable with a %CV of 8.6%. There was no hemolysis interference in the assay when samples were spiked with hemoglobin concentrations of up to 70 mg/dL, based on the %RE of less than or equal to 25% of non-hemolyzed samples. Conclusion Qualification of the ECL method, demonstrates the assay is suitable for the determination of E2 in serum samples from rats and absence of hemolysis interference up to 70 mg/dL of hemoglobin concentration.

The Role of Reticulocyte Hemoglobin Content for the Diagnosis of Functional Iron Deficiency in Hemodialyzed patients.

The effectiveness of reticulocyte hemoglobin content (CHr) had been reported to detect early functional iron deficiency especially among Chronic kidney disease (CKD) patients. CHr is more superior to classic biochemical indices in reflecting transient iron-deficiency status, therefore improving diagnosis and treatment. This study was conducted to determine the sensitivity of CHr in the diagnosis of functional iron deficiency (FID) in hemodialyzed patients. One hundred hemodialyzed patients along with 60 healthy controls were recruited and blood specimens were collected. Venous blood was used for hematological and biochemical investigations collected via 3 ml lavender-top tubes for hematological tests including CBC, blood film, ESR and CHr, and red-top tube for biochemical tests including TIBC, SF and CRP. A statistically significant decrease was noted in CHr values between hemodialysis patients and the control group (24.8 ± 2.0 pg vs. 30.9 ± 1.3 pg, p<0.001). CHr values showed a significant correlations with RBCs, Hb- hemoglobin, Hct- hematocrit level, MCV- mean corpuscular volume, MCH- mean corpuscular hemoglobin, MCHC, RDW- red cell distribution width , SI-Serum Iron, TIBC- Total iron binding capacity and TSAT- Transferrin saturation. The present study showed that CHr in comparison to the conventional hematological and biochemical markers commonly used to diagnose iron deficiency.

Effects of a 12-week worksite aerobic dance programme on blood glucose and lipids in public service employees

This study investigated the effects of a 12-week aerobic dance programme on the serum glucose and lipid profiles of employees (n = 26) of the Ministry of Education and Skills Development (MoESD), Gaborone, Botswana, who registered for the workplace programme. The participants’ baseline anthropometric characteristics expressed as mean ± SD included: age = 35.4 ± 4.3 years; body weight = 77.2 ± 6.3 kg; height = 1.62 ± 2.4 m; BMI = 30.18 ± 3.7 kg/m2; waist circumference = 88.62 ± 1.2cm; hip circumference = 111.03 ± 2.1cm; and % body fat = 8.52 ± 1.1%. A quasi experimental design (one group pre-test-post-test design), in which participants’ serum glucose and lipid profiles were assessed before and after the 12-week aerobic dance programme at 60-70% HRR (Karvonen’s HRR method), was used. Fasting blood samples were collected from the participants using the vacutainer method and biochemically analysed using standard protocols. Using paired t-tests to compare the means of the participants’ pre-test and post-test masurements, results at p ≤ .05 showed significant increases in high density lipoprotein cholesterol (HDL-C) (from 1.09 to 1. 21 mmol.L-1), whereas mean values of low density lipoprotein cholesterol (LDLC) decreased substantialy post-test (from 2.83 to 2.47 mmol.L-1), triglycerides (from .9048 to .7467 mmol.L-1) and blood glucose (from 4.785 to 4.617 mmol.L-1). Conclusively, a 12-week aerobic dance programme could promote healthy blood glucose and lipids in previously sedentary employees.Keywords: Blood glucose, lipids, physical activity, aerobic dance programme, workplace, employees

157. Reducing Blood Culture Contamination Rates Through the Use of a Red Top Tube Discard

BackgroundSepticemia is a major cause of death in the United States and accounts for up to $16.7 billion in annual health care expenses. Blood culture is the gold standard for laboratory diagnosis of bacteremia and resultant septicemia; however, false-positive blood cultures hinder the accurate determination of true bacteremia with often serious implications. The goal of this study was to determine the efficacy of collecting a 1 mL discard in a red tube prior to blood culture collection and to assess its effectiveness in reducing contamination rates in Hartford Hospital Emergency Department (HHED).MethodsDuring the months of June to December 2017 blood cultures were collected by the phlebotomy team using ChloraPrep (chlorhexidine) as the sole disinfecting agent. Blood cultures consisted of BD BACTEC plus Aerobic/F and BD BACTEC Lytic/10 Anaerobic drawn at the same time and monitored on BD BACTEC FX instrument for 5 days. Prior to collecting blood cultures 1 mL of blood was collected in a red top tube and discarded. Monthly and overall contamination rates were then compared with 2016 in which a red top discard tube was not used.ResultsDuring June to December 2016, there were a total of 9,576 blood cultures collected with a total of 178 contaminants and an overall contamination rate of 1.9%. During June to December 2017, there were a total of 9,133 blood cultures collected with a total of 73 contaminants and an overall contamination rate of 0.8%. During both years, our contamination rates were well below the CLSI recommendation; however, a significant reduction in blood culture contamination was observed after the use of a Red Top discard tube (0.8% vs. 1.9%) (Figures 1–3). ConclusionThe cost of a standard blood draw with Red Top tubes is minimal (few cents) while a single collection using an initial specimen diversion device (ISDD) can range from $15 to $18. During the course of this study, the use of a standard Red Top discard cost approximately $456 (2017); if an ISDD was used instead, this would have generated $136,995 in healthcare cost. At our institution, we were able to keep our contamination rates below 1% after the implementation of a standard Red Top discard tube. This suggests that the use of a Red Top discard prior to blood culture collection is an effective means for reducing and maintaining a low blood contamination rate.Disclosures All authors: No reported disclosures.

Profile of vitamin-D deficiency patients in a tertiary care centre, Bhopal: causes and its implications in health

Introduction: Vitamin D deficiency is widespread in individuals irrespective of their age, gender, race and geography. The aim of this study was to assess the status of Vitamin D deficiency in various age group in the people visiting Chirayu Medical College and Hospital, Bhopal for their routine health check-up. Material and Methods: This study was done in the department of Orthopaedics and department of Biochemistry, Chirayu Medical College and Hospital Bhopal. The study comprised of the total of 100 subjects. Five millilitre of venous blood was collected from subjects in plain vials (red top tube) and the serum Vitamin D level was assessed by ELFA method using Biomeriuxminividas. Results: Among the 100 individuals studied in this study there was 66 Females and 34 Males. Among the study group studied it was found that approx. 25% of the total individuals studied are Vitamin D deficient i.e. having serum vitamin D level &lt;20 ng/ml. 20% of the individuals in study group have insufficient vitamin D level i.e. between 20-29 ng/ml. 44% of the total individuals studied have sufficient Vitamin D level (between 30-100 ng/ml) in their sera but in this 44% individuals approx. 11% individuals have their serum vitamin D level in the borderline normal range i.e. between 30-40ng/ml. Conclusion: As Vitamin D deficiency affects all age groups, therefore, strategies such as increasing awareness among masses about adequate exposure to sunlight, rich dietary sources of vitamin D and fortification of foods with Vitamin D which are consumed by majority of Indian population irrespective of the socio-economic status can be adopted and implemented for prevention and control of Vitamin D deficiency throughout the nation.

Effect of Age on Nitric Oxide Level in Murrah Buffalo (Bubalus bubalis) Neonates

Immune system of calf is more susceptible to oxidative stress during neonatal period due to immature defense system against superoxide radicals. Nitric oxide (NO), a component of bactericidal mechanisms of phagocytic leukocytes, plays a pivotal role in cell-mediated immunity. Present research has addressed many NO-related aspects of neonatal adaptation in the postpartum period. The experiment was conducted on twenty Murrah buffaloes selected from NDRI herd. Approximately 15 ml blood was drawn in sterile heparinised vacutainer tubes from each calf born from these buffaloes, by jugular veni-puncture on day 0 (Before colostrum feeding), followed by day 1, 3, 7, 14, 21, 28, 42, 56, 70, 84, 98, 112 and 126 post birth at 6.00 AM in the morning. Plasma was aliquoted and analysed for total NO by modified Griess Reaction as described by Shoker et al. (1997). Plasma nitrate and nitrite levels were significantly elevated (P<0.01) at birth in buffalo calves and decreased rapidly within first week of life with mean values decreasing more than 80%. The mean values declined from 797.08±43.62 μM/L (Precolostral levels) to 78.97±68.97 μM/L on day 126 post- birth. The levels afterwards though less than day 7 but were not comparable to mature buffaloes (1.09±0.41 μM/L to 7.63±2.75 μM/L) even after 126 days post birth exhibiting fluctuations in between. Therefore, we can say that buffalo neonates have an immature immune system as compared to the adult. Leukocytes from neonates produce unusually high concentrations of NO when compared with those produced by adult buffalo, thus, buffalo neonates have an immature immune system. Therefore, further research is needed in this aspect to explore the possibility of nitric oxide involvement in the extra-uterine adjustment of buffalo neonate.

Suitability of Becton Dickinson Vacutainer rapid serum tube for collecting and storing blood samples for antibiotic and anticonvulsant drug monitoring

AimsTo investigate the suitability of newly developed Becton Dickinson Vacutainer rapid serum tube (RST) for therapeutic drug monitoring of antibiotics and anticonvulsants.MethodsTwo pools of citrated whole blood were created by...

Pilot study to assess effects of collection tube types and processing delay on measurements of persistent organic pollutants and lipids in human serum

Glass red top tubes (RTs), traditionally used to draw blood for biomonitoring studies, have some limitations during field sampling (e.g., tube breakage, timely processing may be difficult). This pilot study examined whether serum separation tubes (SSTs) with delayed processing time (48h) can be used instead of red top tubes (RTs) to accommodate field conditions. Using state-of-the-art methodologies, PBDEs, PCBs, OCPs, PFCs, cholesterol and triglycerides were measured to evaluate any differences among 2 test conditions (RTs with 2h processing time; SSTs with 48h processing time). Between the 2 test conditions, we observed high rank correlations among the measured compounds and no statistically significant differences in the levels of measured compounds. We conclude that SSTs with delayed processing time (48h) produce similar results as RTs with short processing time (2h), suggesting that SSTs could be good substitutes for RTs for new epidemiological and biomonitoring field studies. The use of SSTs offers a tremendous opportunity for the use of samples archived in various SSTs.

Prevalence of HIV among people with physical disabilities in Rwanda.

To determine the prevalence of HIV among persons with physical disabilities in Rwanda. Across-sectional HIV diagnostic study. A national referral rehabilitation centre in Rwanda. Persons aged 5 to 49 years with lower or upper limb impairments that were obtaining rehabilitation services at the centre. Blood samples were collected from the subjects who voluntarily accepted to participate in the study. Blood samples (4mls) were collected in vacutainer tubes and centrifuged to obtain serum which was analyzed using standard HIV rapid tests-determine HIV-1/2 Ab/Ag, SD-Bioline and UNI-Gold Recombigen HIV as a tie-breaker. The HIV status of participants--negative or positive. Descriptive statistics were computed to characterize the sample and proportions for the HIV test results. All one hundred and fifty-seven subjects, 59 (37.6%) male and 98 (62.4%) female, completed the study. The HIV prevalence obtained was 5.73%. All participants that tested positive were female and all tested positive for HIV-1. The prevalence obtained was higher than the population prevalence of 3.0% reported for Rwanda. Targeted HIV prevention is required for PWDs in Rwanda, with at least as much rigor as programs targeted towards the general population. Further, this should address the wide range of gender inequalities that make women particularly vulnerable to HIV. Further research needs to be conducted on a larger sample that draws participants from non-institutional settings and from other disability categories; as well as to study more specifically, the risk factors for HIV infection among PWDs in Rwanda.

Blood Collection Tubes Influence Serum Ficolin-1 and Ficolin-2 Levels

The ficolins are members of a recently discovered family of host innate opsonins that can activate the lectin pathway of complement. The ficolins bind many ligands, although they are typically described as binding acetylated sugars. Ficolin-1 (M-ficolin) and ficolin-2 (L-ficolin) are known to bind Streptococcus pneumoniae serotypes 19C and 11A, respectively. While studying the binding of ficolins to pneumococci, we found variations in ficolin-2 binding among serum samples collected in different types of blood collection tubes. Plastic tubes, which contain a silica clot activator, yielded sera with reduced ficolin-2 binding and apparent ficolin-2 levels. We found that the silica clot activator eluted from plastic red-top tubes inhibited ficolin-2 ligand binding, while other related proteins, like mannose-binding lectin (MBL) and ficolin-1, were not affected. These tube types did not affect the concentrations of other related opsonins (C1q, MBL, or ficolin-3 [H-ficolin]). Interestingly, we also found that ficolin-1 levels were increased 2- to 3-fold in plastic serum separator tubes compared to the increases in other tube types. These findings have implications for future ficolin-1 and ficolin-2 studies, as proper sample collection and handling are essential.

Cluster of False-Positive Influenza B Virus Rapid Antigen Test Results in a New York City Hospital

We report a cluster of false-positive influenza B rapid test results associated with the use of red-top tube Vacuette plastic tube Z serum clot activator (item no. 454204). Influenza activity in New York City (NYC), New York, between October 2011 and mid-February 2012 was relatively low, with

Rapid identification and susceptibility testing of positive blood culture caused by gram negative bacteria

Objective To reduce the turnaround time for laboratory diagnosis of bacteremia, the feasibility of rapid identification and susceptibility testing using samples taken directly from positive blood culture bottles was evaluated. Methods The growth of microorganisms in blood culture bottles was screened by the BACTEC 9000 blood culture system. 65 positive blood culture bottles containing gram-negative bacteria were adopted to test. Culture fluid was injected into BD SST vacutainer and centrifuged to pellet blood cells. After collecting required McFarland units, they were cultured on Phoenix 100 NMIC/ID-4(identification-gram-negative bacteria and susceptibility testing) cards using 0.25 McF and 0.5 McF methods respectively. They were also evaluated by the standard method, involving subculture tests from positive blood culture bottles. Results 63 of 65 gram-negative bacteria (96. 9% ) were correctly identified with 0. 25 McF method. 59 of 65 gram-negative bacteria(90.8% ) were correctly identified with 0.5 McF method. For antimicrobial susceptibility testing, the 0.25 McF direct method had an agreement rate more than 94% , the 0.5 McF method was more than 85.7% and direct blood sample KB method was more than 93.8% compared to the standard method. But the overall minor error rate in susceptibility testing of direct blood sample KB method is higher than other methods. Conclusion Applying 0. 25 McF and 0. 5 McF rapid identification and susceptibility test was practical. During to possessing more prominent advantages, laboratory put the 0. 25 McF direct method into practice had a timely, remarkable significance. Key words: Positive blood culture; Joint use; Rapid identification and susceptibility testing