Background The interest for vitamin D has exponentially increased testing demand for 25-hydroxy vitamin D [25(OH)D]. Consequently, many laboratories are switching from LC-MS/MS methods to automated, high-throughput immunoassays. One of the major potential issues with these assays has been the lack of cross-reactivity with 25(OH)D2. Methods We have evaluated the Roche Elecsys vitamin D total II assay for accuracy by comparing 79 patient samples with LC-MS/MS. The cross-reactivity for 25(OH)D2 was evaluated by analyzing samples with high 25(OH)D2 separately and estimating 25(OH)D2 recovery, as well as by spiking of 25(OH)D2. The assay was further evaluated for precision, linearity, sample type, and common interferences. Results There was mostly good agreement between the Elecsys and LC-MS/MS assays (Deming regression: y = 0.95x + 0.70), with an overall bias of 2.3% (−0.84 ng/mL). However, there were 6 out of 79 (7.6%) discordant samples. The Deming regression for samples with high 25(OH)D2 compared to LC-MS/MS showed similar slope and intercept (y = 0.97x − 1.1). The average recovery of 25(OH)D2 for these samples was 90%. The initial precision studies were in general agreement with the package insert, but long-term clinical use showed higher-than-claimed imprecision (11.7%–14.4% at 12 ng/mL and 6.9%–7.6% at 27 ng/mL; claimed: 7.2% and 5.0%, respectively). We observed 1 falsely high result in plasma, an issue previously addressed by Roche in a medical device correction. Conclusions The analytical performance of the Roche Vitamin D assay was acceptable, and the assay had a good cross-reactivity for 25(OH)D2.

Background: Low-titer group O whole blood (LTOWB) is attractive for acute trauma care as it delivers concentrated and balanced hemostatic resuscitation in single large bags. Whether cold-stored LTOWB can sustain platelet counts is unclear.Study Design and Methods: Four cohorts of trauma patients-three historic, one retrospective-were identified by their urgency of blood use. Admission and all subsequent platelet counts over the first 24 h of care were compared with t-tests. The cohorts were as follows: 1292 patients at Maryland Shock Trauma as described by Stansbury and colleagues in 2013; 35 patients enrolled locally in the 1:1:2 arm of the pragmatic randomized optimal plasma and platelet ratios (PROPPR) trial; 34 patients enrolled locally in the 1:1:1 arm of PROPPR; and 59 patients receiving more than 3 units of LTOWB enroute to or at our Level 1 trauma center, 2019-2020.Results: Mean age of LTOWB units transfused was 9 ± 5 days and mean dose was 5 ± 2 units. All four cohorts were profoundly injured (mean Injury Severity Score ≥ 31), with mean first platelet counts 204-228 K/μ and subsequent counts approximately 100 k/μl lower. Through the first 24 h of care, mean platelet counts decreased least, 79 and 83 10 3 /μl, in the 1:1:1 PROPPR and LTOWB cohorts. Mean platelet counts in patients transfused with LTOWB remained stable after the third hour of care.Discussion: LTOWB transfusion was associated with lesser mean decrease in platelet counts during the first 24 h after injury, similar to those observed among patients receiving components 1:1:1 component in the PROPPR study.

Background: Delayed hemolytic transfusion reactions (DHTRs) are reported to be rare occurrences but may be more frequently observed in the trauma setting where patients are heavily transfused, followed over long inpatient admissions, and have frequent subsequent blood counts as they undergo multiple surgical interventions. Study design and methods: We examined the rates of DHTRs on a per transfusion and per patient basis in an academic county hospital with a level 1 trauma center serving a four-state region and over a 3-year period. DHTRs were entered sequentially into a registry as they were observed, and a retrospective review of all new alloantibodies detected was performed to identify any additional DHTRs. The number of units of red blood cells (RBCs), the number of unique patients, types of alloantibodies, and number of transfusions were extracted from blood bank records. Results: Twenty-nine DHTRs were observed from January 1, 2017, through December 31, 2019, from newly observed alloantibodies after a median of 12 red blood cells (RBCs) transfusions per patient. These reactions occurred in response to 24,633 unique transfusions in 6905 unique patients, so the observed rates were about 1:849 RBC transfusions and 1:238 transfused patients. Evidence of delayed hemolysis was seen in five additional patients who were transfused during emergency resuscitation and later found to have had known RBC antibodies. Discussion: We report a higher rate of DHTRs than previously described to demonstrate that DHTRs are not rare in trauma centers.

Waste resources are an attractive option for economical the production of biodiesel; however, oil derived from waste resource contains free fatty acids (FFA). The concentration of FFAs must be reduced to below 1 wt.% before it can be converted to biodiesel using transesterification. FFAs are converted to fatty acid methyl esters (FAMEs) using acid catalysis, which is the rate-limiting reaction (~4000 times slower than transesterification), with a low conversion as well, in the over biodiesel production process. The study is focused on synthesizing and using a bifunctional catalyst (7% Sr/ZrO2) to carry out esterification and transesterification simultaneously to convert waste cooking oil (WCO) into biodiesel using microbubble-mediated mass transfer technology. The results reveal that a higher conversion of 85% is achieved in 20 min using 7% Sr/ZrO2 for biodiesel production. A comprehensive kinetic model is developed for the conversion of WCO in the presence of a 7% Sr/ZrO2 catalyst. The model indicates that the current reaction is pseudo-first-order, controlled by the vapor–liquid interface, which also indicates the complex role of microbubble interfaces due to the presence of the bifunctional catalyst. The catalyst could be recycled seven times, indicating its high stability during biodiesel production. The heterogeneous bifunctional catalyst is integrated with microbubble-mediated mass transfer technology for the first time. The results are unprecedented; furthermore, this study might be the first to use microbubble interfaces to “host” bifunctional metallic catalysts. The resulting one-step process of esterification and transesterification makes the process less energy-intensive and more cost-efficient, while also reducing process complexity.

http://onlinelibrary.wiley.com/doi/10.1111/trf.16232/full