Efficacy of two vitamin D immunoassays to detect 25-OH vitamin D2 and D3.

OBJECTIVES: Assessment of Vitamin D status by measurement of 25-Hydroxyvitamin D (25-OH-D) is widely performed by immunoassay. Yet, the ability of these assays to detect Vitamin D2 (as 25-OH-D2) or Vitamin D3 (as 25-OH-D3) varies. It is important to recognize the ability of an assay to quantitate either form of 25-OH-D to evaluate Vitamin D status of supplemented patients. We evaluated detection of 25-OH-D2 and 25-OH-D3 by two assays in our medical center. DESIGN AND METHODS: The Abbott Architect i1000 SR 25-OH Vitamin D assay and Roche Cobas 8000 Vitamin D assay were compared for their recovery of 25-OH-D2 or D3 from spiked serum samples. Samples with known endogenous concentrations of 25-OH-D2 or D3 by LC-MS/MS were also measured to calculate bias between our assays and LC-MS/MS. RESULTS: Recovery of 25-OH-D3 in spiked samples was similar by Architect (84-87%) and Cobas (90%). Recovery of 25-OH-D2 was lower than 25-OH-D3, and was poorer by Architect (37-40%) than by Cobas (69-71%). In measurement of samples with known 25-OH-D concentrations, performance of Architect and Cobas assays was similar for 25-OH-D3. However, at concentrations >50 nmol/L 25-OH-D2, the Architect assay exhibited large average negative bias (-27%). CONCLUSIONS: While the Architect and Cobas assays performed similarly in detection of 25-OH-D3, the Architect assay was significantly poorer at detecting 25-OH-D2 than Cobas, with poorer recovery and significant negative bias at higher concentrations of 25-OH-D2. This agrees with other studies, and indicates that caution should be used in interpreting Architect 25-OH-D results in patients supplemented with Vitamin D2.

Comprehensive assessment of biotin interference in immunoassays.

BACKGROUND: Biotinylated antibodies and analogues are currently used in many immunoassays while biotin is widely used as a dietary supplement. Thus, biotin interference is an emerging issue for clinical laboratories. METHODS: Various concentrations of biotin solutions were prepared using pooled patient serum samples. All analytes were measured by sandwich or competitive immunoassay on the Roche Cobas 8000 e602 platform. RESULTS: Some of the sandwich immunoassay results were falsely decreased to different extents by different biotin levels, while some of the competitive immunoassay results were falsely increased. The most notable false reductions were in high-sensitivity troponin T, thyroid-stimulating hormone, and follicle-stimulating hormone results, while the most notable false increases were in triiodothyronine and vitamin D results. Other immunoassay results were also affected to some extent by biotin interference. CONCLUSIONS: Biotin can interfere in immunoassays and result in aberrant test results. Clinicians should use caution in interpreting abnormal results in patients who ingest biotin.

The Perfect and Famous Anesthetic Known as Methyl in Boston in 1895.

Extravagant claims were made for proprietary dental anesthetics in Boston, MA, in the late 1800s. For instance, in 1883, Urial K. Mayo introduced an inhaled Vegetable Anaesthetic comprised of nitrous oxide that had been uselessly pretreated with botanical material. This misguided concept may have been inspired by homeopathy, but it was also in line with the earlier false belief of Elton R. Smilie, Charles T. Jackson, and William T.G. Morton that sulfuric ether could volatilize opium at room temperature. In 1895, the Dental Methyl Company advertised an agent they called Methyl, a supposedly perfect topical anesthetic for painless dental extraction. The active ingredient was probably chloroform. Anesthetic humbug did not cease in Boston on Ether Day of October 16, 1846.

Charles T. Jackson and William T.G. Morton Patented the "Ethereal Solution of Opium" of Elton Romeo Smilie.

The Jackson-Morton 1846 patent for surgical insensibility by means of sulphuric ether states that opiates can be added to the ether and co-administered by inhalation. The erroneous concept that ether could carry opiates in its vapor phase at room temperature was proposed in Boston in 1846 by Elton Romeo Smilie (1819-1889), who believed that the opiates were more important than the ether vehicle.

Modelling osteoblast adhesion on surface-engineered biomaterials: optimisation of nanophase grain size.

A double-layered model is proposed for numerically simulating osteoblast adhesion on surface-engineered biomaterials. The proposed model consists of molecular and cellular motions based on theoretical and experimental evidence and creates predictive simulations from sparse experimental data. The comparison of numerical solutions and experimental data reveals that the proposed model can explain the nonlinear behaviour of osteoblast adhesion on material surfaces in respect to nanophase grain size (0-100 nm). The model further provides insight into the optimisation of nanophase grain size on the surface of the biomaterial.

Cardiac Troponin Is a Predictor of Septic Shock Mortality in Cancer Patients in an Emergency Department: A Retrospective Cohort Study.

BACKGROUND: Septic shock may be associated with myocardial damage; however, the prognostic value of cardiac enzymes in cancer patients with septic shock is unknown. In this study, we evaluated the prognostic significance of cardiac enzymes in combination with established prognostic factors in predicting the 7-day mortality rate of patients with septic shock, and we constructed a new scoring system, Septic Oncologic Patients in Emergency Department (SOPED), which includes cardiac enzymes, to predict 7-day mortality rates. METHODS AND FINDINGS: We performed a retrospective cohort study of 375 adult cancer patients with septic shock who visited the emergency department of a comprehensive cancer center between 01/01/2004 and 12/31/2013. The 7-day and 28-day mortality rates were 19.7% and 37.6%, respectively. The creatine kinase myocardial band fraction and troponin-I were significantly higher in patients who died in ≤7 days and ≤28 days than in those who did not. In Cox regression models, troponin-I >0.05 ng/mL plus Predisposition, Infection, Response, and Organ Failure (PIRO2011) or Mortality in Emergency Department Sepsis (MEDS) score was a significant predictor of survival for ≤7 days. With our new SOPED scoring system, the receiver operating characteristic area under the curve was 0.836, higher than those for PIRO2011 and MEDS. CONCLUSIONS: Troponin-I >0.05 ng/mL was an important predictor of short-term mortality (≤7 days). The SOPED scoring system, which incorporated troponin-I, was more prognostically accurate than were other scores for 7-day mortality. Large multicenter studies are needed to verify our results and prospectively validate the prognostic performance of the SOPED score.

Folic acid supplementation prevents the changes in hepatic promoter methylation status and gene expression in intrauterine growth-retarded piglets during early weaning period.

During intrauterine life, genome interacts with maternal signals to influence the mRNA expression levels of specific genes persistently by regulating DNA methylation status. The objective of this study was to examine the responses of glucocorticoid receptor (GR), peroxisome proliferator-activated receptor alpha and gamma (PPARα and PPARγ) promoter methylation, mRNA expression of genes involved in energy metabolism and metabolite concentrations of intrauterine growth-retarded (IUGR) piglets to dietary folic acid supplementation. According to a 2 × 2 factorial arrangement, 16 IUGR and 16 normal birth weight (NBW) piglets were fed a basal diet or a basal diet supplemented with 5 mg/kg of folic acid from weaning (day 14) to day 35 of age. Triglycerides in hepatic tissue and plasma were significantly elevated in control diets-fed IUGR piglets compared with NBW piglets but were decreased by dietary folic acid supplementation. Hepatic mRNA expression levels of GR, PPARα, PPARγ, fatty acid synthase and phosphoenolpyruvate carboxykinase (PEPCK) in IUGR piglets fed a control diet were significantly higher than that in NBW piglets, and promoter methylation status of GR, PPARα and PPARγ in IUGR piglets was reduced significantly compared with NBW piglets. However, the changes in gene expression and DNA methylation status of IUGR piglets were reversed by dietary folic acid supplementation. Hepatic DNA methyltransferase activity was greater with dietary folic acid supplementation regardless of birth weight. Taken together, these results demonstrated that folic acid supplementation during early period of life could prevent the changes of promoter methylation status and gene expressions in the liver of IUGR piglets.

Anti-skin cancer properties of phenolic-rich extract from the pericarp of mangosteen (Garcinia mangostana Linn.).

Skin cancers are often resistant to conventional chemotherapy. This study examined the anti-skin cancer properties of crude ethanol extract of mangosteen pericarp (MPEE) on human squamous cell carcinoma A-431 and melanoma SK-MEL-28 lines. Significant dose-dependent reduction in% viability was observed for these cell lines, with less effect on human normal skin fibroblast CCD-1064Sk and keratinocyte HaCaT cell lines. Cell distribution in G(1) phase (93%) significantly increased after 10 µg/ml of MPEE versus untreated SK-MEL-28 cells (78%), which was associated with enhanced p21(WAF1) mRNA levels. In A-431 cells, 10 µg/ml MPEE significantly increased the sub G(1) peak (15%) with concomitant decrease in G(1) phase over untreated cells (2%). In A-431 cells, 10 µg/ml MPEE induced an 18% increase in early apoptosis versus untreated cells (2%). This was via caspase activation (15-, 3- and 4-fold increased caspse-3/7, 8, and 9 activities), and disruption of mitochondrial pathways (6-fold decreased mitochondrial membrane potential versus untreated cells). Real-time PCR revealed increased Bax/Bcl-2 ratio and cytochrome c release, and decreased Akt1. Apoptosis was significantly increased after MPEE treatment of SK-MEL-28 cells. Hence, MPEE showed strong anti-skin cancer effect on these two skin cancer cell lines, with potential as an anti-skin cancer agent.

Regeneration of N, P and Si near the sediment/water interface of lakes from Southwestern China Plateau.

Lake water, pore water, and sediments were sampled in both polluted and unpolluted lakes from Southwestern (SW) China Plateau. The results show that although the mechanisms of nutrient regeneration were similar in the polluted and unpolluted lakes, the processes, however, were much stronger in the polluted lakes. Nitrogen regeneration was mainly of organic process. Phosphorus regeneration was essentially controlled by iron redox cycling near sediment/water interface. Nutrient upward fluxes were in the order SiO2 > NH4+ > PO4(3-). This study has significance for further investigating the response of nutrient biogeochemistry to the increasing nutrient levels in aquatic environments.

[Influence of functional groups of huatanyuxin decoction on Ca2+ transmembrane influx in rat aorta].

OBJECTIVE: To study the Ca2+ antagonistic effect of functional groups of Huatanyuxin decoction. METHOD: The 45Ca transmembrane influx technique was used to measure the Ca2+ blocking effect of leak, receptor-operated Ca2+ channel (ROC) and potential-dependent Ca2+ channel (PDC) in rat aorta. RESULT: ROC and PDC could be blocked when the complex prescription was used at concentrations of 0.5-5 mg/ml. Among the functional groups, Huoxue group (activating blood) and Xinqi group (promoting and normalizing flow of vital energy) showed better Ca2+ antagonistic effect. CONCLUSION: The mechanism of therapeutic effect of Huatanyuxin decoction may be related to its Ca2+ blocking effect similar to verapamil.

Chu Cheng and Chu's bequeathed book.

Chu Cheng, a native of Yangzhai county in Henan Province, was born in the Nanqi Dynasty. His "Chu's Bequeathed Book" has more than 2200 Chinese characters, was divided into ten verses, reflecting the secrets of Qi-Blood-Yin-Yang. This author tries to introduce and study Chu Cheng's life, his story and his academic views, not only on embryogensis, pulse taking and Five Ti, but also on Yin-Ying-Jing-Xue, obstetrical hygiene and infectious disease and the usage of medicine, etc.